题目内容：

The maths problem is not easy( )
A.to work out B.to be work out C.worked out D.working out

优质解答

选 A

这句话写成it is not easy to work out the maths problem.就容易理解了
有什么疑问还可以问我,帮助到你的话请及时采纳.O(∩_∩)O谢谢