diff --git a/lib/l10n/intl_en.arb b/lib/l10n/intl_en.arb
index 16fb400ac..b1bcf4e02 100644
--- a/lib/l10n/intl_en.arb
+++ b/lib/l10n/intl_en.arb
@@ -5053,5 +5053,6 @@
   "constructUseCorGCDesc": "Correct grammar category practice",
   "constructUseIncGCDesc": "Incorrect grammar category practice",
   "constructUseCorGEDesc": "Correct grammar error practice",
-  "constructUseIncGEDesc": "Incorrect grammar error practice"
+  "constructUseIncGEDesc": "Incorrect grammar error practice",
+  "fillInBlank": "Fill in the blank with the correct choice"
 }
diff --git a/lib/pangea/analytics_data/analytics_data_service.dart b/lib/pangea/analytics_data/analytics_data_service.dart
index 1c10b1208..0f250f121 100644
--- a/lib/pangea/analytics_data/analytics_data_service.dart
+++ b/lib/pangea/analytics_data/analytics_data_service.dart
@@ -14,6 +14,7 @@ import 'package:fluffychat/pangea/analytics_data/level_up_analytics_service.dart
 import 'package:fluffychat/pangea/analytics_misc/client_analytics_extension.dart';
 import 'package:fluffychat/pangea/analytics_misc/construct_type_enum.dart';
 import 'package:fluffychat/pangea/analytics_misc/construct_use_model.dart';
+import 'package:fluffychat/pangea/analytics_misc/construct_use_type_enum.dart';
 import 'package:fluffychat/pangea/analytics_misc/constructs_event.dart';
 import 'package:fluffychat/pangea/analytics_misc/constructs_model.dart';
 import 'package:fluffychat/pangea/analytics_settings/analytics_settings_extension.dart';
@@ -233,12 +234,14 @@ class AnalyticsDataService {
     int? count,
     String? roomId,
     DateTime? since,
+    ConstructUseTypeEnum? type,
   }) async {
     await _ensureInitialized();
     final uses = await _analyticsClientGetter.database.getUses(
       count: count,
       roomId: roomId,
       since: since,
+      type: type,
     );
 
     final blocked = blockedConstructs;
diff --git a/lib/pangea/analytics_data/analytics_database.dart b/lib/pangea/analytics_data/analytics_database.dart
index cb215ae94..5fe681042 100644
--- a/lib/pangea/analytics_data/analytics_database.dart
+++ b/lib/pangea/analytics_data/analytics_database.dart
@@ -10,6 +10,7 @@ import 'package:synchronized/synchronized.dart';
 import 'package:fluffychat/pangea/analytics_data/derived_analytics_data_model.dart';
 import 'package:fluffychat/pangea/analytics_misc/construct_type_enum.dart';
 import 'package:fluffychat/pangea/analytics_misc/construct_use_model.dart';
+import 'package:fluffychat/pangea/analytics_misc/construct_use_type_enum.dart';
 import 'package:fluffychat/pangea/analytics_misc/constructs_event.dart';
 import 'package:fluffychat/pangea/analytics_misc/constructs_model.dart';
 import 'package:fluffychat/pangea/constructs/construct_identifier.dart';
@@ -197,6 +198,7 @@ class AnalyticsDatabase with DatabaseFileStorage {
     int? count,
     String? roomId,
     DateTime? since,
+    ConstructUseTypeEnum? type,
   }) async {
     final stopwatch = Stopwatch()..start();
     final results = <OneConstructUse>[];
@@ -208,6 +210,9 @@ class AnalyticsDatabase with DatabaseFileStorage {
       if (roomId != null && use.metadata.roomId != roomId) {
         return true; // skip but continue
       }
+      if (type != null && use.useType != type) {
+        return true; // skip but continue
+      }
 
       results.add(use);
       return count == null || results.length < count;
diff --git a/lib/pangea/analytics_practice/analytics_practice_page.dart b/lib/pangea/analytics_practice/analytics_practice_page.dart
index 22bca0912..67b7e2d26 100644
--- a/lib/pangea/analytics_practice/analytics_practice_page.dart
+++ b/lib/pangea/analytics_practice/analytics_practice_page.dart
@@ -26,18 +26,28 @@ import 'package:fluffychat/pangea/toolbar/message_practice/practice_record_contr
 import 'package:fluffychat/widgets/future_loading_dialog.dart';
 import 'package:fluffychat/widgets/matrix.dart';
 
-class PracticeChoice {
+class VocabPracticeChoice {
   final String choiceId;
   final String choiceText;
   final String? choiceEmoji;
 
-  const PracticeChoice({
+  const VocabPracticeChoice({
     required this.choiceId,
     required this.choiceText,
     this.choiceEmoji,
   });
 }
 
+class _PracticeQueueEntry {
+  final MessageActivityRequest request;
+  final Completer<MultipleChoicePracticeActivityModel> completer;
+
+  _PracticeQueueEntry({
+    required this.request,
+    required this.completer,
+  });
+}
+
 class SessionLoader extends AsyncLoader<AnalyticsPracticeSessionModel> {
   final ConstructTypeEnum type;
   SessionLoader({required this.type});
@@ -67,12 +77,10 @@ class AnalyticsPracticeState extends State<AnalyticsPractice>
   final ValueNotifier<AsyncState<MultipleChoicePracticeActivityModel>>
       activityState = ValueNotifier(const AsyncState.idle());
 
-  final Queue<
-      MapEntry<PracticeTarget,
-          Completer<MultipleChoicePracticeActivityModel>>> _queue = Queue();
+  final Queue<_PracticeQueueEntry> _queue = Queue();
 
-  final ValueNotifier<PracticeTarget?> activityTarget =
-      ValueNotifier<PracticeTarget?>(null);
+  final ValueNotifier<MessageActivityRequest?> activityTarget =
+      ValueNotifier<MessageActivityRequest?>(null);
 
   final ValueNotifier<double> progressNotifier = ValueNotifier<double>(0.0);
 
@@ -116,13 +124,13 @@ class AnalyticsPracticeState extends State<AnalyticsPractice>
   AnalyticsDataService get _analyticsService =>
       Matrix.of(context).analyticsDataService;
 
-  List<PracticeChoice> filteredChoices(
+  List<VocabPracticeChoice> filteredChoices(
     MultipleChoicePracticeActivityModel activity,
   ) {
     final content = activity.multipleChoiceContent;
     final choices = content.choices.toList();
     final answer = content.answers.first;
-    final filtered = <PracticeChoice>[];
+    final filtered = <VocabPracticeChoice>[];
 
     final seenTexts = <String>{};
     for (final id in choices) {
@@ -137,7 +145,7 @@ class AnalyticsPracticeState extends State<AnalyticsPractice>
           (choice) => choice.choiceText == text,
         );
         if (index != -1) {
-          filtered[index] = PracticeChoice(
+          filtered[index] = VocabPracticeChoice(
             choiceId: id,
             choiceText: text,
             choiceEmoji: getChoiceEmoji(activity.storageKey, id),
@@ -148,7 +156,7 @@ class AnalyticsPracticeState extends State<AnalyticsPractice>
 
       seenTexts.add(text);
       filtered.add(
-        PracticeChoice(
+        VocabPracticeChoice(
           choiceId: id,
           choiceText: text,
           choiceEmoji: getChoiceEmoji(activity.storageKey, id),
@@ -202,7 +210,7 @@ class AnalyticsPracticeState extends State<AnalyticsPractice>
     if (activityTarget.value == null) return;
     if (widget.type != ConstructTypeEnum.vocab) return;
     TtsController.tryToSpeak(
-      activityTarget.value!.tokens.first.vocabConstructID.lemma,
+      activityTarget.value!.target.tokens.first.vocabConstructID.lemma,
       langCode: MatrixState.pangeaController.userController.userL2!.langCode,
     );
   }
@@ -275,10 +283,10 @@ class AnalyticsPracticeState extends State<AnalyticsPractice>
         activityState.value = const AsyncState.loading();
         final nextActivityCompleter = _queue.removeFirst();
 
-        activityTarget.value = nextActivityCompleter.key;
+        activityTarget.value = nextActivityCompleter.request;
         _playAudio();
 
-        final activity = await nextActivityCompleter.value.future;
+        final activity = await nextActivityCompleter.completer.future;
         activityState.value = AsyncState.loaded(activity);
       }
     } catch (e) {
@@ -298,7 +306,7 @@ class AnalyticsPracticeState extends State<AnalyticsPractice>
       activityState.value = const AsyncState.loading();
       final req = requests.first;
 
-      activityTarget.value = req.target;
+      activityTarget.value = req;
       _playAudio();
 
       final res = await _fetchActivity(req);
@@ -314,10 +322,17 @@ class AnalyticsPracticeState extends State<AnalyticsPractice>
     _fillActivityQueue(requests.skip(1).toList());
   }
 
-  Future<void> _fillActivityQueue(List<MessageActivityRequest> requests) async {
+  Future<void> _fillActivityQueue(
+    List<MessageActivityRequest> requests,
+  ) async {
     for (final request in requests) {
       final completer = Completer<MultipleChoicePracticeActivityModel>();
-      _queue.add(MapEntry(request.target, completer));
+      _queue.add(
+        _PracticeQueueEntry(
+          request: request,
+          completer: completer,
+        ),
+      );
 
       try {
         final res = await _fetchActivity(request);
diff --git a/lib/pangea/analytics_practice/analytics_practice_session_model.dart b/lib/pangea/analytics_practice/analytics_practice_session_model.dart
index b438cce39..e0ee08718 100644
--- a/lib/pangea/analytics_practice/analytics_practice_session_model.dart
+++ b/lib/pangea/analytics_practice/analytics_practice_session_model.dart
@@ -6,9 +6,32 @@ import 'package:fluffychat/pangea/analytics_practice/analytics_practice_constant
 import 'package:fluffychat/pangea/practice_activities/message_activity_request.dart';
 import 'package:fluffychat/pangea/practice_activities/practice_target.dart';
 
+class AnalyticsActivityTarget {
+  final PracticeTarget target;
+  final GrammarErrorRequestInfo? grammarErrorInfo;
+
+  AnalyticsActivityTarget({
+    required this.target,
+    this.grammarErrorInfo,
+  });
+
+  Map<String, dynamic> toJson() => {
+        'target': target.toJson(),
+        'grammarErrorInfo': grammarErrorInfo?.toJson(),
+      };
+
+  factory AnalyticsActivityTarget.fromJson(Map<String, dynamic> json) =>
+      AnalyticsActivityTarget(
+        target: PracticeTarget.fromJson(json['target']),
+        grammarErrorInfo: json['grammarErrorInfo'] != null
+            ? GrammarErrorRequestInfo.fromJson(json['grammarErrorInfo'])
+            : null,
+      );
+}
+
 class AnalyticsPracticeSessionModel {
   final DateTime startedAt;
-  final List<PracticeTarget> practiceTargets;
+  final List<AnalyticsActivityTarget> practiceTargets;
   final String userL1;
   final String userL2;
 
@@ -38,7 +61,8 @@ class AnalyticsPracticeSessionModel {
         userL1: userL1,
         userL2: userL2,
         activityQualityFeedback: null,
-        target: target,
+        target: target.target,
+        grammarErrorInfo: target.grammarErrorInfo,
       );
     }).toList();
   }
@@ -59,8 +83,8 @@ class AnalyticsPracticeSessionModel {
     return AnalyticsPracticeSessionModel(
       startedAt: DateTime.parse(json['startedAt'] as String),
       practiceTargets: (json['practiceTargets'] as List<dynamic>)
-          .map((e) => PracticeTarget.fromJson(e))
-          .whereType<PracticeTarget>()
+          .map((e) => AnalyticsActivityTarget.fromJson(e))
+          .whereType<AnalyticsActivityTarget>()
           .toList(),
       userL1: json['userL1'] as String,
       userL2: json['userL2'] as String,
diff --git a/lib/pangea/analytics_practice/analytics_practice_session_repo.dart b/lib/pangea/analytics_practice/analytics_practice_session_repo.dart
index dcf8a1f35..6124234e7 100644
--- a/lib/pangea/analytics_practice/analytics_practice_session_repo.dart
+++ b/lib/pangea/analytics_practice/analytics_practice_session_repo.dart
@@ -1,14 +1,17 @@
 import 'dart:math';
 
 import 'package:fluffychat/pangea/analytics_misc/construct_type_enum.dart';
+import 'package:fluffychat/pangea/analytics_misc/construct_use_type_enum.dart';
 import 'package:fluffychat/pangea/analytics_practice/analytics_practice_constants.dart';
 import 'package:fluffychat/pangea/analytics_practice/analytics_practice_session_model.dart';
 import 'package:fluffychat/pangea/constructs/construct_identifier.dart';
+import 'package:fluffychat/pangea/events/event_wrappers/pangea_message_event.dart';
 import 'package:fluffychat/pangea/events/models/pangea_token_model.dart';
 import 'package:fluffychat/pangea/events/models/pangea_token_text_model.dart';
 import 'package:fluffychat/pangea/lemmas/lemma.dart';
 import 'package:fluffychat/pangea/morphs/morph_features_enum.dart';
 import 'package:fluffychat/pangea/practice_activities/activity_type_enum.dart';
+import 'package:fluffychat/pangea/practice_activities/message_activity_request.dart';
 import 'package:fluffychat/pangea/practice_activities/practice_target.dart';
 import 'package:fluffychat/widgets/matrix.dart';
 
@@ -24,28 +27,23 @@ class AnalyticsPracticeSessionRepo {
       (_) => activityTypes[r.nextInt(activityTypes.length)],
     );
 
-    final List<PracticeTarget> targets = [];
+    final List<AnalyticsActivityTarget> targets = [];
 
     if (type == ConstructTypeEnum.vocab) {
       final constructs = await _fetchVocab();
       final targetCount = min(constructs.length, types.length);
       targets.addAll([
         for (var i = 0; i < targetCount; i++)
-          PracticeTarget(
-            tokens: [constructs[i].asToken],
-            activityType: types[i],
+          AnalyticsActivityTarget(
+            target: PracticeTarget(
+              tokens: [constructs[i].asToken],
+              activityType: types[i],
+            ),
           ),
       ]);
     } else {
-      final morphs = await _fetchMorphs();
-      targets.addAll([
-        for (final entry in morphs.entries)
-          PracticeTarget(
-            tokens: [entry.key],
-            activityType: types[targets.length],
-            morphFeature: entry.value,
-          ),
-      ]);
+      final errorTargets = await _fetchErrors();
+      targets.addAll(errorTargets);
     }
 
     final session = AnalyticsPracticeSessionModel(
@@ -144,4 +142,99 @@ class AnalyticsPracticeSessionRepo {
 
     return targets;
   }
+
+  static Future<List<AnalyticsActivityTarget>> _fetchErrors() async {
+    final uses = await MatrixState
+        .pangeaController.matrixState.analyticsDataService
+        .getUses(count: 100, type: ConstructUseTypeEnum.ga);
+
+    final client = MatrixState.pangeaController.matrixState.client;
+    final Map<String, PangeaMessageEvent?> idsToEvents = {};
+
+    for (final use in uses) {
+      final eventID = use.metadata.eventId;
+      if (eventID == null || idsToEvents.containsKey(eventID)) continue;
+
+      final roomID = use.metadata.roomId;
+      if (roomID == null) {
+        idsToEvents[eventID] = null;
+        continue;
+      }
+
+      final room = client.getRoomById(roomID);
+      final event = await room?.getEventById(eventID);
+      if (event == null || event.redacted) {
+        idsToEvents[eventID] = null;
+        continue;
+      }
+
+      final timeline = await room!.getTimeline();
+      idsToEvents[eventID] = PangeaMessageEvent(
+        event: event,
+        timeline: timeline,
+        ownMessage: event.senderId == client.userID,
+      );
+    }
+
+    final l2Code =
+        MatrixState.pangeaController.userController.userL2!.langCodeShort;
+
+    final events = idsToEvents.values.whereType<PangeaMessageEvent>().toList();
+    final eventsWithContent = events.where((e) {
+      final originalSent = e.originalSent;
+      final choreo = originalSent?.choreo;
+      final tokens = originalSent?.tokens;
+      return originalSent?.langCode.split("-").first == l2Code &&
+          choreo != null &&
+          tokens != null &&
+          tokens.isNotEmpty &&
+          choreo.choreoSteps.any(
+            (step) =>
+                step.acceptedOrIgnoredMatch?.isGrammarMatch == true &&
+                step.acceptedOrIgnoredMatch?.match.bestChoice != null,
+          );
+    });
+
+    final targets = <AnalyticsActivityTarget>[];
+    for (final event in eventsWithContent) {
+      final originalSent = event.originalSent!;
+      final choreo = originalSent.choreo!;
+      final tokens = originalSent.tokens!;
+
+      for (int i = 0; i < choreo.choreoSteps.length; i++) {
+        final step = choreo.choreoSteps[i];
+        final igcMatch = step.acceptedOrIgnoredMatch;
+        if (igcMatch?.isGrammarMatch != true ||
+            igcMatch?.match.bestChoice == null) {
+          continue;
+        }
+
+        final choices = igcMatch!.match.choices!.map((c) => c.value).toList();
+        final choiceTokens = tokens.where(
+          (token) =>
+              token.lemma.saveVocab &&
+              choices.any(
+                (choice) => choice.contains(token.text.content),
+              ),
+        );
+
+        targets.add(
+          AnalyticsActivityTarget(
+            target: PracticeTarget(
+              tokens: choiceTokens.toList(),
+              activityType: ActivityTypeEnum.grammarError,
+              morphFeature: null,
+            ),
+            grammarErrorInfo: GrammarErrorRequestInfo(
+              choreo: choreo,
+              stepIndex: i,
+              eventID: event.eventId,
+            ),
+          ),
+        );
+      }
+    }
+
+    return targets;
+  }
 }
diff --git a/lib/pangea/analytics_practice/analytics_practice_view.dart b/lib/pangea/analytics_practice/analytics_practice_view.dart
index a41f0ec3e..9b46524a9 100644
--- a/lib/pangea/analytics_practice/analytics_practice_view.dart
+++ b/lib/pangea/analytics_practice/analytics_practice_view.dart
@@ -143,8 +143,8 @@ class _AnalyticsActivityView extends StatelessWidget {
                             if (controller.widget.type ==
                                 ConstructTypeEnum.vocab)
                               PhoneticTranscriptionWidget(
-                                text:
-                                    target.tokens.first.vocabConstructID.lemma,
+                                text: target
+                                    .target.tokens.first.vocabConstructID.lemma,
                                 textLanguage: MatrixState
                                     .pangeaController.userController.userL2!,
                                 style: const TextStyle(fontSize: 14.0),
@@ -157,13 +157,8 @@ class _AnalyticsActivityView extends StatelessWidget {
               Expanded(
                 flex: 2,
                 child: Center(
-                  child: ValueListenableBuilder(
-                    valueListenable: controller.activityTarget,
-                    builder: (context, target, __) => target != null
-                        ? _ExampleMessageWidget(
-                            controller.getExampleMessage(target),
-                          )
-                        : const SizedBox(),
+                  child: _AnalyticsPracticeCenterContent(
+                    controller: controller,
                   ),
                 ),
               ),
@@ -179,6 +174,36 @@ class _AnalyticsActivityView extends StatelessWidget {
   }
 }
 
+class _AnalyticsPracticeCenterContent extends StatelessWidget {
+  final AnalyticsPracticeState controller;
+
+  const _AnalyticsPracticeCenterContent({
+    required this.controller,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return ValueListenableBuilder(
+      valueListenable: controller.activityTarget,
+      builder: (context, target, __) => switch (target?.target.activityType) {
+        null => const SizedBox(),
+        ActivityTypeEnum.grammarError => ValueListenableBuilder(
+            valueListenable: controller.activityState,
+            builder: (context, state, __) => switch (state) {
+              AsyncLoaded(value: final activity) => _ErrorBlankWidget(
+                  activity: activity as GrammarErrorPracticeActivityModel,
+                ),
+              _ => const SizedBox(),
+            },
+          ),
+        _ => _ExampleMessageWidget(
+            controller.getExampleMessage(target!.target),
+          ),
+      },
+    );
+  }
+}
+
 class _ExampleMessageWidget extends StatelessWidget {
   final Future<List<InlineSpan>?> future;
 
@@ -220,6 +245,62 @@ class _ExampleMessageWidget extends StatelessWidget {
   }
 }
 
+class _ErrorBlankWidget extends StatelessWidget {
+  final GrammarErrorPracticeActivityModel activity;
+
+  const _ErrorBlankWidget({
+    required this.activity,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    final text = activity.text;
+    final errorOffset = activity.errorOffset;
+    final errorLength = activity.errorLength;
+
+    return Container(
+      padding: const EdgeInsets.symmetric(
+        horizontal: 12,
+        vertical: 8,
+      ),
+      decoration: BoxDecoration(
+        color: Color.alphaBlend(
+          Colors.white.withAlpha(180),
+          ThemeData.dark().colorScheme.primary,
+        ),
+        borderRadius: BorderRadius.circular(16),
+      ),
+      child: RichText(
+        text: TextSpan(
+          style: TextStyle(
+            color: Theme.of(context).colorScheme.onPrimaryFixed,
+            fontSize: AppConfig.fontSizeFactor * AppConfig.messageFontSize,
+          ),
+          children: [
+            if (errorOffset > 0)
+              TextSpan(text: text.characters.take(errorOffset).toString()),
+            WidgetSpan(
+              child: Container(
+                height: 4.0,
+                width: (errorLength * 8).toDouble(),
+                padding: const EdgeInsets.only(bottom: 2.0),
+                decoration: BoxDecoration(
+                  color: Theme.of(context).colorScheme.primary,
+                ),
+              ),
+            ),
+            if (errorOffset + errorLength < text.length)
+              TextSpan(
+                text:
+                    text.characters.skip(errorOffset + errorLength).toString(),
+              ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
 class _ActivityChoicesWidget extends StatelessWidget {
   final AnalyticsPracticeState controller;
 
@@ -366,6 +447,20 @@ class _ChoiceCard extends StatelessWidget {
           isCorrect: isCorrect,
         );
 
+      case ActivityTypeEnum.grammarError:
+        final activity = this.activity as GrammarErrorPracticeActivityModel;
+        return GameChoiceCard(
+          key: ValueKey(
+            '${activity.errorLength}_${activity.errorOffset}_${activity.eventID}_${activityType.name}_grammar_error_$choiceId',
+          ),
+          shouldFlip: false,
+          targetId: targetId,
+          onPressed: onPressed,
+          isCorrect: isCorrect,
+          height: cardHeight,
+          child: Text(choiceText),
+        );
+
       default:
         return GameChoiceCard(
           key: ValueKey(
diff --git a/lib/pangea/analytics_practice/grammar_error_practice_generator.dart b/lib/pangea/analytics_practice/grammar_error_practice_generator.dart
index 66ec9c5db..30880ab50 100644
--- a/lib/pangea/analytics_practice/grammar_error_practice_generator.dart
+++ b/lib/pangea/analytics_practice/grammar_error_practice_generator.dart
@@ -1,41 +1,50 @@
+import 'package:flutter/material.dart';
+
 import 'package:fluffychat/pangea/practice_activities/message_activity_request.dart';
 import 'package:fluffychat/pangea/practice_activities/multiple_choice_activity_model.dart';
 import 'package:fluffychat/pangea/practice_activities/practice_activity_model.dart';
-import 'package:fluffychat/widgets/matrix.dart';
 
 class GrammarErrorPracticeGenerator {
   static Future<MessageActivityResponse> get(
     MessageActivityRequest req,
   ) async {
-    final igcMatch = target.igcMatch;
-    assert(igcMatch.bestChoice != null, 'IGC match must have a best choice');
-    assert(igcMatch.choices != null, 'IGC match must have choices');
+    assert(
+      req.grammarErrorInfo != null,
+      'Grammar error info must be provided for grammar error practice',
+    );
 
-    final errorSpan = igcMatch.errorSpan;
-    final correctChoice = igcMatch.bestChoice!.value;
+    final choreo = req.grammarErrorInfo!.choreo;
+    final stepIndex = req.grammarErrorInfo!.stepIndex;
+    final eventID = req.grammarErrorInfo!.eventID;
+
+    final igcMatch =
+        choreo.choreoSteps[stepIndex].acceptedOrIgnoredMatch?.match;
+    assert(igcMatch?.choices != null, 'IGC match must have choices');
+    assert(igcMatch?.bestChoice != null, 'IGC match must have a best choice');
+
+    final correctChoice = igcMatch!.bestChoice!.value;
     final choices = igcMatch.choices!.map((c) => c.value).toList();
 
-    final choiceTokens = target.tokens.where(
-      (token) => choices.any(
-        (choice) => choice.contains(token.text.content),
-      ),
-    );
-
-    assert(
-      choiceTokens.isNotEmpty,
-      'At least one token should match the error choices',
-    );
+    final stepText = choreo.stepText(stepIndex: stepIndex - 1);
+    final errorSpan = stepText.characters
+        .skip(igcMatch.offset)
+        .take(igcMatch.length)
+        .toString();
 
     choices.add(errorSpan);
     choices.shuffle();
     return MessageActivityResponse(
       activity: GrammarErrorPracticeActivityModel(
-        tokens: choiceTokens.toList(),
+        tokens: req.target.tokens,
         langCode: req.userL2,
         multipleChoiceContent: MultipleChoiceActivity(
           choices: choices.toSet(),
           answers: {correctChoice},
         ),
+        text: stepText,
+        errorOffset: igcMatch.offset,
+        errorLength: igcMatch.length,
+        eventID: eventID,
       ),
     );
   }
diff --git a/lib/pangea/practice_activities/message_activity_request.dart b/lib/pangea/practice_activities/message_activity_request.dart
index fef5c5243..47eebe6db 100644
--- a/lib/pangea/practice_activities/message_activity_request.dart
+++ b/lib/pangea/practice_activities/message_activity_request.dart
@@ -1,5 +1,11 @@
+import 'package:flutter/material.dart';
+
 import 'package:sentry_flutter/sentry_flutter.dart';
 
+import 'package:fluffychat/l10n/l10n.dart';
+import 'package:fluffychat/pangea/choreographer/choreo_record_model.dart';
+import 'package:fluffychat/pangea/morphs/morph_features_enum.dart';
+import 'package:fluffychat/pangea/practice_activities/activity_type_enum.dart';
 import 'package:fluffychat/pangea/practice_activities/practice_activity_model.dart';
 import 'package:fluffychat/pangea/practice_activities/practice_target.dart';
 
@@ -35,23 +41,67 @@ class ActivityQualityFeedback {
   }
 }
 
+class GrammarErrorRequestInfo {
+  final ChoreoRecordModel choreo;
+  final int stepIndex;
+  final String eventID;
+
+  const GrammarErrorRequestInfo({
+    required this.choreo,
+    required this.stepIndex,
+    required this.eventID,
+  });
+
+  Map<String, dynamic> toJson() {
+    return {
+      'choreo': choreo.toJson(),
+      'step_index': stepIndex,
+      'event_id': eventID,
+    };
+  }
+
+  factory GrammarErrorRequestInfo.fromJson(Map<String, dynamic> json) {
+    return GrammarErrorRequestInfo(
+      choreo: ChoreoRecordModel.fromJson(json['choreo']),
+      stepIndex: json['step_index'] as int,
+      eventID: json['event_id'] as String,
+    );
+  }
+}
+
 class MessageActivityRequest {
   final String userL1;
   final String userL2;
   final PracticeTarget target;
   final ActivityQualityFeedback? activityQualityFeedback;
+  final GrammarErrorRequestInfo? grammarErrorInfo;
 
   MessageActivityRequest({
     required this.userL1,
     required this.userL2,
     required this.activityQualityFeedback,
     required this.target,
+    this.grammarErrorInfo,
   }) {
     if (target.tokens.isEmpty) {
       throw Exception('Target tokens must not be empty');
     }
   }
 
+  String promptText(BuildContext context) {
+    switch (target.activityType) {
+      case ActivityTypeEnum.grammarCategory:
+        return L10n.of(context).whatIsTheMorphTag(
+          target.morphFeature!.getDisplayCopy(context),
+          target.tokens.first.text.content,
+        );
+      case ActivityTypeEnum.grammarError:
+        return L10n.of(context).fillInBlank;
+      default:
+        return target.tokens.first.vocabConstructID.lemma;
+    }
+  }
+
   Map<String, dynamic> toJson() {
     return {
       'user_l1': userL1,
@@ -60,6 +110,7 @@ class MessageActivityRequest {
       'target_tokens': target.tokens.map((e) => e.toJson()).toList(),
       'target_type': target.activityType.name,
       'target_morph_feature': target.morphFeature,
+      'grammar_error_info': grammarErrorInfo?.toJson(),
     };
   }
 
@@ -72,7 +123,8 @@ class MessageActivityRequest {
         other.userL2 == userL2 &&
         other.target == target &&
         other.activityQualityFeedback?.feedbackText ==
-            activityQualityFeedback?.feedbackText;
+            activityQualityFeedback?.feedbackText &&
+        other.grammarErrorInfo == grammarErrorInfo;
   }
 
   @override
@@ -80,7 +132,8 @@ class MessageActivityRequest {
     return activityQualityFeedback.hashCode ^
         target.hashCode ^
         userL1.hashCode ^
-        userL2.hashCode;
+        userL2.hashCode ^
+        grammarErrorInfo.hashCode;
   }
 }
 
diff --git a/lib/pangea/practice_activities/practice_activity_model.dart b/lib/pangea/practice_activities/practice_activity_model.dart
index 36d284f0b..602165b7c 100644
--- a/lib/pangea/practice_activities/practice_activity_model.dart
+++ b/lib/pangea/practice_activities/practice_activity_model.dart
@@ -354,10 +354,19 @@ class LemmaPracticeActivityModel extends MultipleChoicePracticeActivityModel {
 
 class GrammarErrorPracticeActivityModel
     extends MultipleChoicePracticeActivityModel {
+  final String text;
+  final int errorOffset;
+  final int errorLength;
+  final String eventID;
+
   GrammarErrorPracticeActivityModel({
     required super.tokens,
     required super.langCode,
     required super.multipleChoiceContent,
+    required this.text,
+    required this.errorOffset,
+    required this.errorLength,
+    required this.eventID,
   });
 }
 
diff --git a/lib/pangea/practice_activities/practice_generation_repo.dart b/lib/pangea/practice_activities/practice_generation_repo.dart
index 3ff418594..35a961940 100644
--- a/lib/pangea/practice_activities/practice_generation_repo.dart
+++ b/lib/pangea/practice_activities/practice_generation_repo.dart
@@ -130,6 +130,10 @@ class PracticeRepo {
       case ActivityTypeEnum.grammarCategory:
         return MorphCategoryActivityGenerator.get(req);
       case ActivityTypeEnum.grammarError:
+        assert(
+          req.grammarErrorInfo != null,
+          'Grammar error info must be provided for grammar error activities',
+        );
         return GrammarErrorPracticeGenerator.get(req);
       case ActivityTypeEnum.morphId:
         return MorphActivityGenerator.get(req);
diff --git a/lib/pangea/practice_activities/practice_target.dart b/lib/pangea/practice_activities/practice_target.dart
index d6a0a1540..87c1ce7e7 100644
--- a/lib/pangea/practice_activities/practice_target.dart
+++ b/lib/pangea/practice_activities/practice_target.dart
@@ -1,9 +1,7 @@
 import 'package:flutter/foundation.dart';
-import 'package:flutter/material.dart';
 
 import 'package:collection/collection.dart';
 
-import 'package:fluffychat/l10n/l10n.dart';
 import 'package:fluffychat/pangea/constructs/construct_identifier.dart';
 import 'package:fluffychat/pangea/events/models/pangea_token_model.dart';
 import 'package:fluffychat/pangea/morphs/morph_features_enum.dart';
@@ -85,18 +83,6 @@ class PracticeTarget {
         (morphFeature?.name ?? "");
   }
 
-  String promptText(BuildContext context) {
-    switch (activityType) {
-      case ActivityTypeEnum.grammarCategory:
-        return L10n.of(context).whatIsTheMorphTag(
-          morphFeature!.getDisplayCopy(context),
-          tokens.first.text.content,
-        );
-      default:
-        return tokens.first.vocabConstructID.lemma;
-    }
-  }
-
   ConstructIdentifier targetTokenConstructID(PangeaToken token) {
     final defaultID = token.vocabConstructID;
     final ConstructIdentifier? cId = morphFeature == null