It is very difficult for a person to know how fast a car is traveling为什么是is travelling,原因!

it is very difficult for me. English is very difficult ,but I like it best (同义句转换English is very difficult ,but it is ------ ------- -----。 This question is not difficult. It's very s______. Tim doesn't like b_____,it is very difficult it,very,difficult,to,is,well,learn,english,him,for It is very difficult for her______(climb) up the mountain. The question is not easy.It’s very ______.A.not difficult B.difficulty C.difficult I think that it is _____ problem for us.a quiet difficult b quiet a difficult c very difficult a it is difficult it is difficult at The____Lesson is very difficult but very important.You must learn it by heart.(twelve) this question is very difficult ( ) This question is very difficult.I can't answer it.This question is ___ difficult ___me ___answer. To be a man is not easy,it's very difficult!living naturally is more difficult什么意思 It is very difficult to love someone .It's tired to love a human! ! The work is very difficult..it's _____(possible) to finish it in a day. I found it is very difficult to understand what the foreigner said.（×）为什么不能是“found it is very difficult to...”,不是find可接从句吗? It is very difficult for pedestrians to know how fast a car is traveling.