message: Translate some German within teacher's task unit
diff: <div *ngFor="let task of model.tasks" class="question-answer">
  <mat-form-field matLine class="question">
  - <textarea matInput id="name" placeholder="Frage hier eingeben." [(ngModel)]="task.name"></textarea>
  + <textarea matInput id="name" placeholder="Enter question here" [(ngModel)]="task.name"></textarea>
  </mat-form-field>
  <div class="actions">
  <div class="check-answer">
  <mat-checkbox [(ngModel)]="answer.value" name="value_{{idx}}"></mat-checkbox>
  <mat-form-field>
  - <input matInput placeholder="Antwort hier eingeben." [(ngModel)]="answer.text">
  + <input matInput placeholder="Enter answer here" [(ngModel)]="answer.text">
  </mat-form-field>
  </div>
  </div>
  