Also, too: cũng before the verb

Cũng means "also" or "too". It goes after the person and before the verb or adjective, and before words like không, đang or muốn, never at the end of the sentence the way English "too" does: Tôi cũng thích phở. I like phở too. Hôm nay em cũng bận. I'm busy today too.

With a noun, it goes before là: Chị Lan cũng là giáo viên. Lan is a teacher too.

Cũng points back to something just said, so the situation tells you what it adds. If a friend says Mai mình đi Đà Lạt, then Em cũng đi means "I'm going too".

Three neighbours use the same word. For "not … either", put cũng before không: Em cũng không biết. To say "me too" without repeating the sentence, say Em cũng vậy (you'll also hear cũng thế, more in the North). And cũng with an adjective on its own can mean "fairly, OK": Cũng được. It's alright.

Don't mix it up with cùng, with the falling tone, which means "together": Mình cùng đi nha.