2 say 'yes' - to say yes to an idea, plan, suggestion etc [≠ refuse]:

- agree to do something
e.g.: No one really knows why he agreed to do the film.
- agree to
e.g.: My sister won't agree to our mother going into a nursing home.

3 decide together - to make a decision with someone after a discussion with them

- agree to do something
e.g.: We agreed to meet again the following Monday.
- agree on
e.g.:They managed to agree on a date for the wedding.
- agree that
e.g.: It was agreed that elections would be held in May.
-agree a price/plan/strategy etc
e.g.: We agreed a new four-year contract.

4 be the same - if two pieces of information agree with each other, they match or are the same

agree with
e.g.:Your story doesn't agree with what the police have told us.

5 agree to differ/disagree - if two people agree to differ, they accept that they have different opinions about something and stop arguing about it

- agree with something (phrasal verb)
1 to believe that a decision, action, or suggestion is correct or right
e.g.: I don't agree with hitting children.
2 not agree with somebody - if a type of food does not agree with you, it makes you feel ill:
e.g.: Green peppers don't agree with me.
3 if an adjective, verb etc agrees with a word, it matches that word by being plural if the word is plural etc

synonyms: see eye to eye, be of the same opinion, be of the same mind, etc

opposites: deny, dispute, differ, disagree, dissent, contradict, refute, retract, rebut