（）可以提高婴幼儿的社会认知。
A、逛街
B、体育运动
C、亲子游戏
D、散步
参考答案：C
底面边长为2m，高为1m的正三棱锥的全面积为______m2．
Usually John would be late for meetings. But this time, to my surprise, he arrived on time.
A little B. much C. ever D. even
