依据神经系统在人体中的位置和功能的不同，可以分为（）两类
A.交感神经系统
B.中枢神经系统
C.副交感神经系统
D.周围神经系统
参考答案：B, D
He went to ______ yesterday. [ ]
A.town
B.a town
C.the town
D.towns
Come as early as possible ;________,the better.
A． early
B． the earliest
C．earlier
D．the earlier
