是用动名词还是动词不定式working(to work) out the math problem like this

是用动名词还是动词不定式working(to work) out the math problem like this This is very easy to work out the math problem.有什么错? The studients found ____ easy to work out this math problem I found()impossble for()to work out the math problem the math problem is too hard to work ------out I have __________(困难) working out the math problem. He thought he had d______ working out the math problem. ---This Math problem isn’t easy for Jack to work out, is it? problem,out,you,time,math,solve,this,how,need,work,much,to 高中英语改错题You can work out the math problem in this method.请指出错 This is another way of _____ (work) out the math problem.快 _____ this way, you can work out the math problem.  A．O