--- Could you tell me what he said just now?
--- Sorry, I ______ what was going on outside.
| A．had thought | B．was thinking | C．thought | D．think |
--- I called you last night, but nobody answered the phone.
--- Sorry, ________.
| A．I must be sleep at that moment. | B． I must have slept at that moment. |
| C．I must have been asleep at that moment. | D．I must have fallen asleep at that moment. |
We need to strike a ______ between the needs of the community and the rights of the individual.
| A．silence | B． difference | C．balance | D．weakness |
We ______ while Mr. Evan read the exam results.
| A．held our breath | B． wasted our breath |
| C．caught our breath | D．took our breath |
You may ______ your teachers for help when you have problems.
| A．turn up | B． turn down | C．turn to | D．turn off |
Was it______ Tom’s carelessness______ your keys were lost?
| A．because; which | B． for; what | C．because of; that | D．since; why |