Many, few: nhiều / ít + noun

Nhiều (many, a lot of) and ít (few, not much) go before the noun, like a number: nhiều người (a lot of people), ít tiền (not much money). Unlike a number, they usually need no classifier: nhiều bạn (lots of friends), though one is fine too: nhiều cuốn sách.

English has "many" for things you count and "much" for things you don't. Vietnamese uses nhiều for both, and ít for both "few" and "little": nhiều xe (a lot of motorbikes), nhiều nước (a lot of water). Bare ít leans to "not much"; for a friendly "a little, some", say một ít or một chút: Cho em một ít nước. Can I have a little water?

They often come after có: Ở đây có nhiều quán ăn ngon. There are lots of good places to eat here. In speech the có is often dropped: Sài Gòn nhiều xe máy quá!

For a place that's crowded or empty, with people or with traffic, Vietnamese uses đông (crowded) and vắng (quiet): Chợ đông quá. The market is packed. Thiếu (short of) and thừa (more than needed) go before a noun in the same way: thiếu tiền (short of money).

After a verb, nhiều and ít say how much you do it instead: ăn nhiều (eat a lot).