Children are always asking all kinds of questions because they are ______ about the world they live in.
| A．curious | B．worried |
| C．anxious | D．careful |
Only after he had spent several nights working on the math problem _______ to wonder whether the problem was wrongly set.
| A．that he began | B．did he begin | C．then he began | D．so that he began |
__________ David could remember, he had never said an angry word to that customer.
| A．As far as | B．As long as | C．As well as | D．As much as |
________ enthusiasm when he heard our advice, he didn’t take any notice.
| A．To lack | B．Lacking of | C．To lack in | D．Lacking |
You must have waited here for a long time, __________?
| A．mustn’t you | B．needn’t you | C．didn’t you | D．haven’t you |
Although a teenager, Fred could resist ______ what to do and what not to do.
| A．to be told | B．being told |
| C．having been told | D．to have been told |