霾老师物理课：今天咱们讲丁达尔现象和光的直线传播。。。
Life is a song--Sing it.
Life is love--Enjoy it.
Life is a game--Play it.
Life is a sacrifice--Offer it.
Life is a challenge--Meet it.
Life is a dream--Realize it.
sTilLaliVe‘s photo album
Life is love--Enjoy it.
Life is a game--Play it.
Life is a sacrifice--Offer it.
Life is a challenge--Meet it.
Life is a dream--Realize it.
sTilLaliVe‘s photo album