The snow storm left, a lot of damage to this area.
A. caused B. causing C. to cause D. to have caused
—You seemed to be impressed by his skill.
—No. It was his courage ________ his skill that really impressed me.
A. but also B. except for C. as well as D. rather than
—Who______ it be that is knocking at the door?
—It ______ be Father, but I’m not sure.
A. can; must B. can; may C. must; can D. may; must
Once harm is _______ to the eco-system, all species will ________, including man himself.
A. made; be in danger B. done; be dangerous
C. caused; be endangered D. done; be in danger
The stamp on the letter is an art, from _______ we can get a lot of cultural knowledge.
A. whom B. which C. them D. those
It is believed that a new kind of drug ______ by the scientists and they are hopeful that they will succeed in a few months.
A. has been developed B. is being developed
C. is developing D. has developed
