John _______ to waiters every time he is satisfied with the service.
A. tip
B. tips
C. tipping
D. tippd
查看答案
We paied 20 dollars as the _____(tip) to the waiter.
_____(tip) is a common culture in North America.
He left a _____(tip) to the boy for mercy.
引起失眠的病因常见有
A. 情志所伤
B. 饮食不节
C. 病后年迈
D. 禀赋不足
E. 心虚胆怯
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