So vs Such

Both words make something stronger — close to very. The main choice is about what comes next: so goes with an adjective or adverb, while such goes with a noun phrase. Same idea, two shapes: so cold / such a cold day. For quantities, use the special patterns so much and so many.

So + adjective or adverb

In the main pattern, use so directly before an adjective or adverb.

Such + noun phrase

Use such when a noun follows. Add a/an for a singular countable noun; use no article with plurals and uncountables.

So much / so many

To intensify a quantity, so pairs with much (uncountable) or many (countable).

so … that / such … that

Both can introduce a result. The same shape rule applies — so with the adjective, such with the noun phrase.

In conversation the that is often dropped: I was so tired I fell asleep. Both versions are fine.

Common mistakes

Using so before a/an + adjective + noun. In this pattern, use such.

So can still come before a noun through a quantity word: so many people and so much traffic.

Using such with a bare adjective. With no noun, use so.

Dropping the article after such. A singular countable noun still needs a/an.

With plural or uncountable nouns there's no article, so such nice people and such bad weather are already correct.

Quick exercise

Fill in so, such or such a.

1. It was ___ beautiful day.
2. The movie was ___ boring.
3. She has ___ many friends.
4. He's ___ good teacher.
5. I was ___ tired that I fell asleep.
6. They were ___ nice people.