______ I always felt I would pass the exam, I never thought I would get an A.
A. While B. Once C. If D. Until
The weather in Beijing is cooler than ________ in Guangzhou.
| A．this | B．it | C．that | D．one |
We found ________ necessary to protect the environment.
| A．it | B．this | C．that | D．what |
-Which would you like, rice or noodles? --_______is OK. I'm hungry.
| A．Either | B．Neither | C．Both | D．All |
I don't think it very expensive to buy a family computer here.
-- Really? I'll buy _______ next week.
| A．it | B．this | C．one | D．mine |
Lucy knew nothing about it ________ her sister told her.
| A．because | B．until | C．if | D．since |