The argument is extremely heated ______ there are necessary conditions of existence such as water on the Mars.
| A．that | B．whether | C．if | D．which |
—Tom often drives carelessly.
—Tell him he ________ answer for it if he goes on behaving like that.
| A．shall | B．should | C．will | D．must |
He ________ your car by mistake because he didn't have the keys.
| A．mustn't have taken | B．shouldn't have taken |
| C．couldn't have taken | D．needn't have taken |
—The similarities between social networks are striking.
—That ________ come as no surprise，because they are all products of the Internet.
| A．should | B．shall | C．may | D．must |
—Hi，Joan.Any idea where Tom is?
—He ________ on the playground.I saw him there playing football just now.
| A．shall be | B．should have been |
| C．must be | D．might have been |
—Guess what？I came first in that contest.
—Great！You ________ a lot during the past two weeks.
| A．must practise | B．should practise |
| C．should have practised | D．must have practised |