运动负荷试验时，极量心率粗略计算法为（）.
A.190-年龄
B.200-年龄
C.210-年龄
D.220-年龄
E.250-年龄
参考答案：D
— Have you got any particular plans for the coming holiday?
— Yes. ________, I'm going to visit some homes for the old in the city. [ ]
A. If ever
B. If busy
C. If anything
D. If possible
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