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课时提升作业(四)
必修1 Unit 4
Ⅰ. 单项填空
1. (2013·嘉兴模拟)A housing bubble is an economic situation _________occurs when house prices rise much too fast.
A. which B. where C. what D. why
2. (原创)Because _________after being unable to find a pen for the countless time, inventor Andrew Jewson came up with the novel idea of shrinking a ballpoint pen to the size of a headphone jack.
A. being depressed B. having depressing
C. depressed D. depressing
3. (2013·芜湖模拟)Many friends sent me e-mails to_________me on passing the contest.
A. celebrate B. reward
C. express D. congratulate
