前无古人，后无来者

前无古人，后无来者

Literally means:

without a parallel either in history or in the future

Actually means:

A thing had never been done in the past, nor will there ever be anyone to do it again. Or something had never been seen before, and will not be seen in future.

It describes something unique or unparalleled. It is often used to refer something either extremely good or notoriously bad. It shows admiration when used to describe a good thing or a good person, and it carries a tone of irony when used for a bad one. Commendatory.

一件事情前面没有人做过，以后也不会有人做，或者一样事物以前没有出现过，将来也不会出现。

形容事情（或人）独一无二。多指好的和不好的事情，如非常杰出的，或非常荒唐的。对好事多带有赞赏的口气，对不好的事带有讽刺。