Describing nouns with verbs

To use verbs to describe nouns, we alter the verb stem accordingly:
Present tense: V+는 N
Past tense: V+(으)ㄴ N
Future tense: V+(으)ㄹ N

Examples
제가 먹는 음식이에요.
It’s food that I’m eating.
제가 먹은 음식이에요.
It’s food that I’ve eaten.
제가 먹을 음식이에요.
It’s food that I will eat.
어제 본 영화를 다시 보고 싶어요.
I want to watch the movie I saw yesterday again.
공부한 외국어를 아주 어려웠어요.
The foreign language I was studying was very difficult.