---Jack，do you mind if I use our computer for a while?
---Not at all.___.
| A．You’ll use it. | B．Go ahead. | C．Come on. | D．Take it easy. |
According to the air traffic rules, you ___ switch off your mobile phone before boarding.
| A．may | B．can | C．would | D．should |
When I was young, I was told that I ______ play with matches
| A．wouldn't | B．needn't | C．mustn't | D．daren't |
-What sort of house do you want to have? Something big?
--Well, it ______ be big--that's not important.
| A．mustn't | B．needn't | C．can't | D．won't |
—I can’t find my purse anywhere.
—You __ have lost it while shopping.
| A．may | B．can | C．should | D．would |
Although this ____ sound like a simple task, great care is needed.
| A．must | B．may | C．shall | D．should |