... referenced in the same sentence. Other information can be derived from the mood and aspect of the verb, from the lexical category which the verb is a member of and, more generally, from several ... identify the errors, if any, present in the former and to formulate some hypotheses about their causes. On the basis of these hy- potheses, the Tutor selects the next exercise which will test the ... example, the kind of clause (main, coordinate, subordinate), whether the clause has a verb to be solved, the voice and form of the clause, the kind of event described by the clause, the time...