The water will be further polluted unless some measures ____

The water will be further polluted unless some measures ____.(上海1992)
A.will be taken B.are taken
C.were taken D.had been taken
【B】.are taken
unless是连词,相当于if...not,意为“除非；如果不”.注意主句是将来时,从句要用一般现在时代替.如：
I shall go there tomorrow unless I'm too busy.
如果我不太忙,明天将到那儿去.
Unless you go at once you will be late.如果你不马上走,就会迟到的.

B

The water will be further polluted unless some measures ____. (上海1992)
A. will be taken B. are taken

C. were taken D. had been taken

【B】. are taken

unless是连词，相当于if...

B