Plural means one, two or three (1+).

Pronoun +      Be

1. We are late.
2. You are late.
3. They ire late.

We, you, and they refer to two, three or more persons.

4. John and I are here.

We are here.

5. John and you are here.

You are here.

6. John and Ashley are here.

They are here.

Note: you can be singular or plural.