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單項選擇題

You didn't have to write the essay if you didn't want to. It was（）

A.compulsory
B.suitable
C.alternative
D.optional

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單項選擇題

Income tax rates are（）to one's annual income.

A.related
B.dependent
C.based
D.associated

單項選擇題

The speaker talked about sports in general and about football（）

A.in brief
B.in sequence
C.in short
D.in particular