it's certainly not for me!

it's certainly not for me! It‘s certainly not for me!能否写成It is not certainly for me!为什么 It's certainly not for me 意思应该是? It is certainly not for me是否等于It is not certainly for me?为什么 It's certainly not for me.这里面certainly不是副词吗?怎么能修饰be动词呢? It is not certainly for me和It is certainly not for me一样或差不多吗 翻译：Well,it‘s certainly done something for me,but now what it It's not easy for me to learn math. who cares…OK it`s not for me It's for me. Don't tell me it's not worth trying for You can't tell me it It's not easy for me to play soccer.(改为同义句) It's _____ _____