On the third floor there are two rooms, _____ is used as a meeting-room.
| A．one of them | B．the larger of which | C．and a larger of them | D．the largest one of which |
It will take a long time for the effective use of natural resources _________.
| A．to be made | B．to make | C．being made | D．making |
_________ hard one may work, one cannot master a foreign language in a year or two.
| A．Though | B．As | C．While | D．However |
That is just _________ challenging job all the workers want to get. Do you have anyone in _________ mind for it?
| A．a; the | B．the; / | C．the; the | D．a; / |
--Jack! I have left my key to the office at home.
-- Don’t worry. I _________ it for you. Wait a minute.
| A．get | B．am going to get | C．will get | D．am getting |
--Did Mary return late last night?
--No. It was not yet 7 o’clock _________ she arrived home.
| A．before | B．when | C．that | D．until |