问题补充:
The environment will be further polluted unless some measures .
A. are taken
B. will be taken
C. are being taken
D. should be taken
答案:
(答案→)A. are taken
B. will be taken
C. are being taken
D. should be taken
解析:考查时态:句意:环境将被进一步污染,除非一些措施被采取。主句是一般将来时,Unless引导的是条件状语从句,用一般现在时代替将来时。选A。