沉降观测水准点的设置应满足下列基本要求：水准点的数目应（），以便检核。
A、不少于3个
B、不少于5个
C、不多于3个
D、不多于5个
参考答案：A
We had a hard time the last time we went camping, because the fire ______ during the freezing night.
A．went over
B．went out
C．went on
D．went through
叙述推拿练功方法中坐裆势的基本动作。
