Samuel Clemens，______ Mark Twain, wrote many popular stories.
| A．was known as | B．known as |
| C．was known for | D．known for |
___________ 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 |