肌张力异常分为（）
A.2种
B.3种
C.4种
D.5种
E.6种
参考答案：B
设函数f（2x）=x2+ex，则f’（x）=（）
A.A
B.B
C.C
D.D
Because our work is very busy, so we need to relax at midday.
A．We are very busy
B．Our work being busy
C．Our work so very busy
D．Because our work so very busy,
