In the lecture, the professor told us __
题型：选择题
问题：
In the lecture, the professor told us _______ to protect the environment.[ ]
A. how important was it
B. how important it was
C. how important
D. how important was
In the lecture, the professor told us _______ to protect the environment.[ ]
A. how important was it
B. how important it was
C. how important
D. how important was