左手拿得到，但用右手却拿不到？
参考答案：
右手
自然光与偏振光的区别指（）。
A.光的颜色
B.光的强度
C.光的吸收
D.光波的振动取向
To become complete mature, a child has to pass through several different stages in development at different times and at different rates of speed．
