-i'v been working on this problem since last night.---it must be a difficult one _____A to solve B to be sovled C solving D for solving为什么选A 能否具体说明？

I've Been Working on the Railroad 歌词 i am working on .I had been working on it for five years before we got to the shooting stagstage has been working on his degree是什么意思 -i'v been working on this problem since last night.---it must be a difficult one _____A to solve B to be sovled C solving D for solving为什么选A 能否具体说明？ I/we should have been working.是什么意思 I have been working for two days. i have been working lots as I ___ on my report next week so I won’t be able to meet you any day.A.am working B.will be working C.was working D.have been working顺便翻译下 ---What are you doing these days?---I have been ______ the ceremony for the Foreign Language and Culture Festival.A.working on B.working up C.working out D.Working Because i have been working Because i have been working hard 请翻译英语诗歌《I've been working on the railroad》I've been working on the railroad All the live-long day I've been working on the railroad Just to pass the time away Can't you hear the whistle blowing? Raise up so early in the mom C Have you been working on the project?__.I will have a rest in ten minutes.A:No,I haven't B:Yes,I do make difference.Now,I am working on I'm working on a novel.翻译 I've been working extra hard lately.什么时态? I've been working hard for a whole year. I have been working here for 7 years.改为同义句怎摸说形如I have been working here— — —