每分钟心率的正常变动范围为().
A、40~50次
B、60~100次
C、110~120次
参考答案:B
---- Do you know _______ they got to know each other?
---- It was last year_______ they both taught Chinese in Scotland.
A.When it was that, when
B.when it was that, while
C.When it was that, that
D.When it was that, as
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