What are subjects of verbs?

Question

Gramatically what is noun agreement?

Answer 1

Well in a sentence the verb or the action is usually being done by someone - that someone is the subject.

(Yo) Estoy comiendo.

I am the subject so the verb estar had to be conjugated in the first person singular - I.

if you were talking about a boy - he would be the subject so you would have to say

(Él) Está comiendo.

As far as agreement with nouns you have to make any adjective agree with your noun as far as gender and number goes:

Eg, Las manzanas (noun) rojas (adjective). The red apples.

The apples (noun) are feminine and plural so red (adjective) had to be feminine and plural.

I hope that isn't too confusing to you and at least helps a bit