單項選擇題I have spent a lot of time（）working on this problem.

A.at
B.–（不填）
C.on
D.with


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1.單項選擇題She likes to spend time（）with her grandchildren.

A.play
B.to play
C.playing
D.played

2.單項選擇題China is（）the east of Asia.

A.in
B.to
C.on
D.at

3.單項選擇題That place is（）the south of the city.

A.at
B.in
C.on
D.to

4.單項選擇題I'm tired. I（）working very hard.

A.have
B.am
C.had
D.have been

5.單項選擇題They（）for hours.

A.have been driving
B.have been driven
C.drove
D.drive