高一英语 he tried to work out the problem in five min

高一英语 he tried to work out the problem in five min He found () difficult to work out the problem in such a shor I tried my best to work out the maths problem but I failed.同 He is busy to work out the difficult problem. 改错 He often o to help me work out the problem. He found it difficult to work out the problem. li lei tried hard ____(work)out the problem who can work out the problem ____ five minutes? A.on B.to C. He can work out the problem a( although he tired his best,he failed to work out the problem He tired his best to work out the problem and ( ) he finishe He is clever.He can work out the problem.合并为一句