You can't be _____ when you camp _____ at high altitude,when the air is thin.A.enough careful,atB.too careful,atC.careful enough,onD.too careful,on

问题描述:

You can't be _____ when you camp _____ at high altitude,when the air is thin.
A.enough careful,at
B.too careful,at
C.careful enough,on
D.too careful,on