用例描述用户对系统的期望，被用于软件需求建模，一个用例对应于软件能够为参与者提供的一项服务。
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Whether he comes or not ________ matter too much.
A. doesn’t
B. don’t
C. didn’t
D. haven’t
“News of victories ________ pouring in as our army advances,” the company commander said.
A. keep
B. keeps
C. kept
D. have kept
Ten minutes ________ an hour when one is waiting for a phone call.
A. is
B. are
C. is like
D. seems
Most of the wood ________ to make furniture.
A. were used
B. have been used
C. had been used
D. was used
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