我当然会帮你。这还用说吗？

Of course I'll help you. That goes without saying.

《牛津词典》

当然，这还用说。

Yes, that goes without saying.

youdao

当然了，你英语口语培训加班的那几个小时是要算钱的，这还用说嘛~。

Of course, it goes without saying that you'll be paid for the extra hours you work.

youdao