Unit:5 The Passive of modal verbs

1. of, relating to, or characteristic of mode or manner
2. grammar (of a verb form or auxiliary verb) expressing a distinction of mood, such as that between possibility and actuality. The modal auxiliaries in English include can, could, may, must, need, ought, shall, should, will, and would.

Present Formula: Modal+be+past participle

Example:
Revision for spelling can be done on a computer.

Problem with reservation should be reported to the restaurant manager.

Remember:
Must: means "have to" in 10%of its uses. In this meaning, it is often used in expressions like: I must admit and I must say.

90% of the uses of "Must" are for speculation:

Things must be hard for couples who marry young.