A:①②③
B:②③④
C:①②④
D:①②③④
I like sunny days.
看图,选词填空。
A: What ____ your uncle do?
B: He is ____ engineer.
①“海市蜃楼”是光的色散现象;②“杯弓蛇影”是光的反射现象;③“凿壁借光”是光的直线传播现象;④“井底之蛙”是光的反射现象;⑤“立竿见影”是光的折射现象;⑥“囊萤照读”中的“萤火虫”是光源.
--I think it's really necessary. It is reported that the food that Chinese people
every year is enough to feed 200 million people for a year.