From the ________ look on his face, I knew that he must have been threatened by someone.

The other day，my friend John drove his car down the street at _______I thought was a dangerous speed and surprised everyone in the car.

Because of the snow,many parts of the countryside are only _________ by helicopter.

Tom often helps ______ with my English after school.

_ the English examination, I would have gone tothe concert last Sunday.