请问句中的‘That's That's how I know the job must have b

问题补充：

请问句中的‘Thats Thats how I know the job must have been done.

答案：

那就是我怎么知道这个工作必须做的原因.

======以下答案可供参考======

供参考答案1:

这就是我怎样...