第1个回答 2014-04-30
We must listen to the teacher carefully in class.
第2个回答 2014-04-30
We should listen to the teacher carefully
第3个回答 2014-04-30
we should listen the class carefully
第4个回答 2014-04-30
We are supposed to listen to the teacher very carefully in class.
第5个回答 2014-04-30
We should listen to the teacher carefully.