---I’m terribly sorry to have put you to so much trouble. ---______. You didn’t mean to, did you?a. forget it b. no trouble c. all right d. you’re welcome
Although he is very young, he is much more experienced than others __working ability.
Good use___ the natural resources to improve people’s life in this area.
A great number of students said they were forced to practice the piano .
—When shall we restart our business ? —Not until we our plan .
When changing lanes , a driver should use his turning signal to let other drivers know .