______ at the door before entering please.
| A．Knocked | B．Knock | C．Knocking | D．To knock |
While shopping ,people sometimes can’t help_____into buying something they don’t really need.
| A．persuade | B．persuading | C．being persuaded | D．to be persuaded |
The experiment turned out to be______failure, but “_________failure goes before success”
A a , a B /, / C a , / D / , a
Was it because his mother was ill ______ he didn’t go to school?
| A．so | B．that | C．why | D．when |
Our teacher asked us to give all the used books to ______ needed them.
| A．all | B．whom | C．those | D．those who |
We have got plenty of time. We ______ hurry.
| A．needn’t | B．mustn’t | C．shouldn’t | D．cannot |