is difficult to do sth .还是to doingis difficult to do sth .还是to doing sth,

To do today's homework without teacher's help is difficult的主语为什么是to do today's homework? To do today's homework without teacher's help is difficult的主语为什么不是homework? 为什么 To do today's homework without the teacher's help is very difficult.的主语中心词为to do? is difficult to do sth .还是to doingis difficult to do sth .还是to doing sth, it is difficult to do /doingit is difficult 后接to do 还是doing it is difficult to do sth对还是it difficult to do sth对 it difficult to do sth 和it is difficult to do sth 的区别 To do today's homework without the teacher's help is very difficult.中主语的中心词 Things difficult for a woman to do it more difficult to do man is difficult! 翻译下 it is difficult to you to do the job to do the job is difficult改为同义句( ）difficult（ ）do the job It's difficult to do sth 还是It's difficult doing sth Is difficult to forget the past~But i know it's hard but i gotta do it是什么意思 用It's difficult to do sth.造句 nothing is difficult if you try your best to do difficult to do /to be doneDo you think English is difficult to learn?为什么这里不是Do you think English is difficult to be learnt?English 是被学啊. 是it is difficult to me to do sth还是it is difficult to me for sth还是it is difficult to me to sth it is so difficult for sb to do sth,difficult用so形容对吗?