-What do you think of bacteria ,( )good or bad?-( )to say ,but one thing is certain :with out

题目

-What do you think of bacteria ,( )good or bad?-( )to say ,but one thing is certain :with out
bacteria,the world would be quite diferent from what it is.
A Are they,hard B Is it,hardly C Is it ,hard D Are they ,hardly

答案

C 前面的bacteria是集合名次,单数的,所以要用it is 后面的句型是It's hard to do something,因为前面提到is it了所以这一句的主语it可以省略