The fog was so heavy this morning that drivers could hardly ______ thethings just ten meters away from them.

_____the problem of land erosion getting more serious, the government is searching for a way to deal with it.

Is your mother still a teacher?— ______.

Excuse me, could you please ______ shout in the classroom –Sorry! I will keep quiet from now on.

_____is the distance between these two villages?