Self study The Infinitive

More examples with perfect and passive forms:

He is said to have sold all his houses.

She was sorry to have said it.

He is known to have been working in this field for many years.

He wants to be informed about any problems immediately.

He asked to be informed of their arrival.

She is lucky to have been given such an opportunity.

Note: Modal verbs

All of the infinitive forms are used with modal verbs in order to express certain meanings of modal verbs. For example:

He can write reports.

He must be writing a report now.

He should have written a report yesterday.

This report might have been written by one of our freelance workers.

Read about the forms of the infinitive with modal verbs in Modal Verbs Introduction and see examples with the forms of the infinitive in Possibility and Strong Probability in the subsection Modal Verbs in the section Grammar.

Simple and compound infinitive forms, together with the verbs "would, could, might", are used in the forms expressing unreal condition. For example: If I had known it, I would have stayed home. (See Conditional Sentences in the section Grammar.)