Yesterday Grandma ______ in the park.[ ]
A. walk
B. walks
C. walked
答案：C
—Do you know Bill well?
—Yes. We _______ friends since primary school.
[ ]
A. have turned
B. have made
C. became
D. have been
由高级神经系统活动特性所决定的行为活动的能量和时间特性描述的是个体的( )。
A．人格B．技能C．动机D．气质
