题目内容:
The biggest challenge weall face is to prevent further environmental disasters. We ________ take action before it is too late.
A.can
B.must
C.may
D.might
参考答案:
答案解析:
The biggest challenge weall face is to prevent further environmental disasters. We ________ take action before it is too late.
A.can
B.must
C.may
D.might