Radium salts, which have been found to _____ in bones, give rise to cancers of the bone.
| A．pile up | B．build up | C．keep up | D．pull up |
Young people who have got jobs may realize university lessons can’t be the only preparation for all of the situations ________ appear in the working world.
| A．where | B．when | C．that | D．What |
—We all had a lot of fun at the barbecue yesterday. Pity you weren’t there.
—I really should have gone with you but I _____ on some remaining problems.
| A．worked | B．was working | C．would work | D．would have worked |
—I can’t get on well with some of my classmates. They just leave me in the cold. 
—________ But what’s the reason?
| A．Sorry to hear that. | B．How about that? | C．Don’t mention it. | D．Never give up! |
I don’t think that your lecture _______ the audience, for they appeared quite puzzled.
| A．got across to | B．got close to | C．got away with | D．got along with |
—Can I use the telephone on the table, sir? 
—Under no circumstances _________ to use the telephone in the office for personal affairs.
| A．anyone is allowed | B．nobody is allowed |
| C．is anyone allowed | D．is nobody allowed |