A) unless B) lest C) provided D) whereas

17. ________ the case is settled out of court, it can often take years before it comes to trial.

A) Except that B) Unless C) Until D) But for E) Despite the fact that

18. Put on your rain()coat ________ it rains.

A) because B) as C) lest D) in case E) in condition

19.________ gas leaks and similar accidents should occur, some responsible persons should regularly inspect all the laboratories.

A) Unless B) In case C) Provided D) Until

20. ________ in one leg, he never had a chance to get a job.

A) Weak and lame B) He was weak and lame

C) Though weak and lame D) Weak and lame as he was

21. The production of television commercials must be professional ________ they aim at promoting good service, or public education.

A) when B) no matter C) if D) whether

22. The prices have been going up, so that the richer you get, the less rich you are than ________ you think you ought to be.

A) that B) / C) what D) which