can, may, should

John ....... come to the party, but no-one is sure.

• may

• is

• must

You ........ be polite to your classmates.

• should

• can

• are

Mary ....... play the guitar very well.

• can

• is

• isn't

You ...... work so hard. You look tired.

• shouldn't

• can

• should

• may

I .... lift this heavy box. Will you help me?

• may

• can't

• didn't

I ...... open this window. It's stuck.

• hadn't

• will not

• can't

• must

Whose bag is it? I don't know, it ........ be Susan's.

• may

• will

• won't

• is

I'm afraid I ............... understand. What are you talking about?

• may not

• must

• don't

• should

Your mum gives good advice. You .................... follow it.

• aren't

• may

• are

• should

Greg has an exam tomorrow. He ....................... go to the cinema tonight.

• shouldn't

• isn't

• must

• have