—My son is addicted to computer games. He is hopeless, isn't he?
—Yes, _____ he is determined to give up and start all over.
| A．if | B．when | C．even if | D．unless |
We human beings should be very careful with what we do with nature, _____power is beyond our understanding.
| A．that | B．which | C．whose | D．where |
Scientists are convinced ______ the positive effect of laughter ______ physical and mental health.
| A．of; at | B．by; in |
| C．of; on | D．on; at |
Everybody in the village likes Jack because he is good at ______ and telling jokes.
| A．making up | B．turning up |
| C．putting up | D．showing up |
Kidswillbe______abouteverythingwhentheyreacha certainage.
| A．anxious | B．curious |
| C．cautious | D．conscious |
Mary said she was by no means angry; ______, she was glad to be able to make herself clearly understood.
| A．all in all | B．for one thing |
| C．on the contrary | D．by the way |