He is crying. Do you know what happened him? [ ]
A.at
B.with
C.about
D.to
答案:D
下列运算正确的是[ ]
A.3a﹣a=3
B.a3÷a3=a
C.a2×a3=a5
D.(a+b)2=a2+b2
3月3日,国家海洋局公布了对包括 及附属岛屿在内的71个岛屿的标准化名称。
A.钓鱼岛
B.黄岩岛
C.台湾岛
D.南沙群岛