______ is known to us is that tobacco contains nicotine and other harmful products, so you should give up smoking.
| A．As | B．It | C．What | D．Which |
—I can start to work next Monday.
—____________ then. I am glad to be able to offer you the job.
| A．You can't be serious. | B．You're welcome. |
| C．That's right. | D．It's settled. |
We can't _________ his mistakes, which were made because he was too careless with his work.
| A．overcome | B．understand | C．tolerate | D．recognize |
Nobody could believe what Chloe says because she is ___________ changing her mind.
| A．regularly | B．steadily | C．constantly | D．suddenly |
Would it be ___________ for you to pick me up at four o'clock and take me to the airport?
| A．free | B．vacant | C．handy | D．convenient |
Occasions are rare _____________ I can spend a whole day with my daughter.
| A．that | B．where | C．when | D．which |