手机只有在通话时才与网络有联系。()
参考答案:错
It has been proved taking exercise regularly does good to one’s health.
A.whether
B.when
C.what
D.that
下列反射活动属于条件反射的是( )
A.狗吃到肉,分泌唾液
B.青梅入口,分泌唾液
C.看见糖果,分泌唾液
D.强光射眼,迅速闭眼