对妊高征病人，下列症状中，哪项不属于先兆子痫（）.
A.头晕
B.呕吐
C.胸闷
D.视力模糊
E.头痛
参考答案：C
He _____ football regularly for many years when he was young.
A．was playing
B．has played
C．played
D．had played
什么叫内力？什么叫应力？什么叫强度？
