여자는 남자가 든 동아리에 들 것 같다.
The woman seems to join the club that the man joined
든 >> 들(다) + (으)ㄴ
들다 here means "join (a club)"
사진 동아리에 들다
join the photography club
나는 글 쓰는 것을 좋아해서 문예반에 들었다
I joined a literary club because I enjoy writing.
(으)ㄴ : modifier suffix for past tense.
내가 든 동아리 : the club that I joined (past)
내가 들 동아리 : the club that I will join (future)
내가 드는 동아리 : the club that I am joining (present)