So …! and too …: quá after or before

After an adjective, quá turns it into an exclamation: Ngon quá! So good! Đẹp quá! How beautiful! It's how you react to something in the moment, often with ôi or trời ơi in front: Trời ơi, nóng quá!

When you're complaining, the same words mean "too": at the market, Mắc quá! means "That's too expensive!" (in Hà Nội, Đắt quá!). Only the situation tells you whether it's "so" or "too".

Before an adjective, quá often means "too, more than it should be": quá nhiều đường (too much sugar), quá xa (too far). In speech it's also often just a strong "very": quá đẹp, stunning; quá tuyệt, amazing. The situation tells you which. Before a time or a place, quá means "past": quá giờ (past the time), Đi quá rồi! (We've gone past it!).

Compared with rất and lắm, which describe, quá reacts. When you recommend a place, Quán này rất ngon or ngon lắm fits; tasting the food yourself, you say Ngon quá! In Saigon, quá trời is stronger still: Đông quá trời! It's so crowded!