动物的体色与周围环境的色彩非常相似,这种体色被称为____ ,这样的动物不易被其他动物所发现,这对它____ 敌害或者____ 猎物都是十分有利的。
On his _________ from Australia we gave him a welcome party.
I like the _______.
从高空中自由落下一个小球,经过10s后小球落到地面,取g=10m/s2,求:
You must make the bed every day.(改为同义句)
You ____ ____ make the bed every day.