Question

英语高手快来，快帮忙解决一道选择题，谢谢啦！！急那~~~

I think ______ is our duty to keep our classroom clean and tidy.A that B this C it D on

Answer 1

C

Answer 2

i think it is our duty to keep our classroom claean and tidy.

Answer 3

选C哈。 作形式主语。 比如 这是我们的责任去学习吧。It is our duty to study.

Answer 4

C 宾语从句中的形式主语

Answer 5

明显C

Answer 6

选C ，作形式主语