The problem is ___ he has enough time.A.ifB.whetherC.thatkey ;A这是不是表语从句?表语从句能用if吗?

The problem is difficult.I can't work it out.（连成一句）The problem isn't ___ ___ ___ ___ to work out. The math problem is so difficult that he can't___ ___ ___.他算不出来. what is the problem The maths problem is wery easy.They can work it out=The maths problem is __ __ for ___ to __ ___急 Is this problem ___ the teacher explained last week?加THE呢 the math problem is ___ __ ___difficult 这个数学题有点难 Lily is working ___ the maths problem.A.at B.in C.on D.of The problem is above my ___ .I really can'tunderstand it. 1.This math problem is more difficult than that one.This math problem ___ ___ ___ ____ that one.1.This math problem is more difficult than that one.This math problem ___ ___ ___ ____ that one.2.Mary is taller than the other girls in our class .Mary i we have a problem ___ the computer difficult as the problem is The problem is ( )( )或( )( )(有点)( ) Choice,The problem is choice! 英语翻译The ___ ___ is ___ ___ ___ ___ ___. The h( ) problem is the most important one.It is effective to work when we are well. The math problem isn't easy for me to work out (保持原句意思)The math problem is ___ ____ for me to work out The problem they raised at the meeting is worth ___.填discussing还是being discussed?答案是discussing为什么? the method ___ you solved the problem is good a. with that. b. that, c. with which. d. which