Today many serious childhood diseases _______ by early immunization.
A.are preventing
B.can prevent
C.prevent
D.can be prevented

A new hospital _______ in this area lately.
A.has built
B.have built
C.has been built
D.have been built

We wish we _______ a large house, but we can’t afford it.
A.have
B.having
C.had
D.to have

Her job was so _______ that she decided to quit it.
A.interesting
B.satisfactory
C.stressful
D.wonderful

How many exercises _______ so far?
A.you have done
B.have you done
C.are you doing
D.did you do

______(53)
A.explain
B.express
C.perform
D.tell

________(51)
A.ages
B.centuries
C.times
D.years

Choose the letter A, B, C or D to show the underlined part that needs correcting.
Because the highway system was built 40 years ago, most of the roads now need to repair.
A.Because
B.was built
C.most of
D.to repair

Choose the letter A, B, C or D to show the underlined part that needs correcting.
The books writing by Mark Twain are very popular in the world.
A.The books
B.writing
C.Mark Twain
D.are

Choose the letter A, B, C or D to show the underlined part that needs correcting.
The Americans agree that a wife should maintain her beautifully after marriage.
A.The Americans
B.a wife
C.maintain
D.beautifully