Though it was in the midnight, ________ there were a lot of people in the street.

The monitor said that the learning method he used         improved his maths.

To improve your spoken English, you’d better listen to the tape ______. 

As is often pointed out, knowledge is a two-edged weapon which can be used ________ for good or evil．

— I’d like to go home now. — Why not stay here for the night? It is so late now. ____, it is raining so hard.