点A与点B关于直线a对称,则直线a垂直线段AB,且平分线段AB。[ ]
正确
Do you want to know ___________ in the future? A special mirror invented by the French scientists can help you.
A. what you will look like
B. what will you look like
C. how you will look like
机械制造中常用的特殊性能用钢分为不锈耐酸钢、耐热钢和耐磨钢三类。