Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
Not only______to determine the depth of the ocean floor, but it is also used to locate oil.
A.seismology is used
B.using seismology
C.is seismology used
D.to use seismology

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
He was the last man______ the ship.
A.who leave
B.to leave
C.leaving
D.left

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
They ______ tired now because they ______ in the garden since 8 o’clock.
A.are/ worked
B.were/were working
C.are/have been working
D.were/worked

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
If I weren’t afraid of travelling by air, I ______ to go to American by ship, which took me much longer time.
A.I hadn’t had
B.I wouldn’t have had
C.I shouldn’t have had
D.I wouldn’t have

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
The man _______ his car outside hasn’t come back for it yet.
A.whom he left
B.who he left
C.who left
D.whose

How long could divers stay underwater in Halley’s bell?
A.Just a few seconds
B.Only a few minutes
C.For days on end
D.For hours at a time

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
This class,_____is a prerequisite for microbiology, is so difficult that I would rather drop it.
A.that
B.when
C.where
D.which

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
Why not ________ the meeting until Thursday morning?
A.postpone
B.postponing
C.you postpone
D.do you postpone

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
If some endangered species ______ in zoos, it would help to ensure their future survival.
A.will be kept
B.are kept
C.had been kept
D.were kept

Mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the following questions.
Ann has a lot of books, she has never read.
A.most of that
B.most of these
C.most of which
D.which most of them