Hello, fellas. In this session we are going to learn about the abridgement of noun clauses. A noun clause is a clause used as the subject, object or complement of a sentence. It can begin with a question word (who, whom, what, which, where, when, whose, why or how), that, if or whether.
Noun clauses beginning with one of the question words or whether can be abridged. However, the abridgement is only possible if these requirements are fulfilled:
1) The main clause and the noun clause have the same subject or the subject of the noun clause is the same as the object of the main clause; and
2) The noun clause contains a modal verb either can/could or should.
There are 3 steps in the abridgement of noun clauses:
1) Omit the subject;
2) Omit the modal verb; and
3) Change the verb into an infinitive.
1) I know what I should do. (I know what to do.)
2) She told me when I should go. (She told me when to go.)
3) Students learn how they could write journals. (Students learn how to write journals.)
Betty Schrampfer Azar, Understanding and Using English Grammar: Third Edition