73.Look!I live in the room window faces to the south.

A./that

B.which

C.of which

D.whose

74.Look at the watch.Don’t yosee it is watch Helen lost the other day?

A.as the same;as

B.the same;as

C.the same;which

D.as the same;that

75.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

76.I prefer a color TV,I have to buy a black and white one this time.

A.As

B.Since

C.Because

D.Although

77.I had just started back for the house to change my clothes I heard the voices.

A.as

B.for

C.while

D.When

78.The lady will have to wait all day the doctor Works faster.

A.if

B.unless

C.whether

D.that

79.It was not until 1936 basketball became a part of the Olympic Games.

A.which

B.than

C.that

D.then

80.The day must be breaking,the birds have begun singing.

A.because

B.as

C.for

D.since