that's that idiom (also that was that)
C1 就这样吧；就这样定了；再没有什么可说的
an expression that shows that something has ended
I won't agree to it and that's that (= I won't discuss it any longer). 我不会同意这件事的，不要再说了。
江苏热线英汉汉英双解词典包含207361条英汉翻译词条，涵盖了常用英语单词及词组短语的翻译及用法，是英语学习的必备工具。