教师职业道德的基本特征是（）①全局性②超前性③导向性④强制性
A.①②③
B.②③④
C.①③④
D.①②④
参考答案：A
若ab=10，a+b=3，则a2b+ab2的值为______．
—Tom, What did you do last Sunday morning ?
— I _______ my grandma with my parents .
A．visited
B．visit
C．will visit
D．have visited
