I think it necessary to do sth.还是 I think it is necessary to do sth.

题目

I think it necessary to do sth.还是 I think it is necessary to do sth.
如果是前者,为什么从句中不要be动词?

答案

两个都可以
第一句里面it做宾语 necessary to do sth做宾补
第二句it is ...是宾语从句