6. The factory has to stop working for a day _________ the machines can be cleaned.
| A.in case | B.supposing that | C.the moment | D.so that | 
___________ was most important to her, she told me, was her family.
| A.It | B.This | C.What | D.As | 
The man _______ the little boy and said , “You are so clever and lovely . I love you very much.”
| A.glared at | B.aimed at | C.stared at | D.laughed at | 
________ work has been done to improve the people’s living standard.
| A.A large amount of | B.A large number of | C.A great deal | D.A great many | 
He made another wonderful discovery , ____ of great importance to science.
| A.which I think is | B.which I think it is | 
| C.which I think it | D.I think which is | 
Most villagers agree that horses are far more pleasant _______ than tractors, but they are less efficient.
| A.looking at | B.to look at | C.to be looked at | D.being looked at |