英语完形填空 求讲解In our lives,pain and suffering is the key to all

英语完形填空 求讲解
In our lives,pain and suffering is the key to all windows,and sometimes even ___43___ growth,without it,there’s no way of life.We can’t avoid ___44___ or problems.So,next time you are ___45___ a problem or difficulty,remember the butterfly.Struggle a little–then fly!
43.A.repeats B.recommends C.requires D.represents
44.A.happiness B.difficulties C.pleasure D.hope
45.A.served with B.growing into C.bringing in D.faced with
这套完型原文网上有,翻译有可能要结合文章主旨,...求这一段的翻译和这三道题的讲解~