The engineers made two big plans for the dam, ____ was never put in force.
| A．one of them | B．which | C．one of which | D．every one of which |
_____from what he said, he must be the thief who has stolen the car.
| A．Judging | B．Judged |
| C．To judge | D．Judge |
Can you make sure _______ the gold ring?
| A．where Alice had put | B．where had Alice put |
| C．where Alice has put | D．where has Alice put |
It’s no good ________about his grades.
| A．worrying | B．to worry |
| C．to be worried | D．worry |
If he ________tomorrow, I could talk to him about it.
| A．comes | B．was coming |
| C．should come | D．would come |
Ann is said ________ research in Africa, and she will come back next month.
| A．to do | B．to be doing |
| C．to have done | D．done |