1To be in a relationship or keep close company with someone — used both for friendships and for romantic dating.
二人は大学時代から付き合っている。
The two of them have been dating since college.
彼女に告白して、付き合ってほしいと伝えた。
I confessed my feelings to her and told her I wanted us to date.
近所の人たちと長年付き合ってきた。
I've kept close ties with the neighbors for many years.
あの二人はもう半年付き合っているらしい。
I heard those two have been going out for six months now.
2To go along with someone's invitation or plans, accompanying them even if reluctantly.
友達の買い物に付き合って、一日中歩き回った。
I went along with my friend's shopping and walked around all day.
残業に付き合ってくれてありがとう。
Thanks for staying to help me with overtime.
気が乗らなかったが、飲み会に付き合った。
I wasn't in the mood, but I went along to the drinking party anyway.