It‘s certainly not for me 副词certainly 修饰什么?

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'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 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 certainly not off the table at this point什么意思 Having a trip abroad is certainly good .abroad是副词在这里修饰什么呢? -Would you mind helping me?-Certainly还是Certainly not.表示 当然不介 it certainly is 英语语法it's certainly that 有这种用法吗?