be careful.is it low enough( )you to be able to step over it A to B for C of D with(解析
问题描述：
be careful.is it low enough( )you to be able to step over it A to B for C of D with(解析
we had tried everything but it made no ( )it is still the same now A use B good C result D difference(解析
答
B
It is +形容词 for sb. to do sth.对某人来说做某事是...
It is very important for him to speak English more.