友達と
友達と公園に行った。
I went to the park with a friend.
Together with one or more friends; indicates accompaniment in an action.
友達と映画を見に行った。
I went to see a movie with a friend.
友達と話すのが楽しい。
Talking with friends is fun.
Used in casual conversation. The particle と directly follows the noun indicating the companion.
Related Phrases
Pro Tip
Avoid confusion with other particles
The particle と is often confused with で. Use と for accompaniment (e.g., 友達と行く = go with a friend) and で for means/method (e.g., バスで行く = go by bus).
Gold Rule
と for accompaniment
Always use と after a noun to indicate the person you are doing something with. It cannot be omitted in standard Japanese.
Word Origin
友達 (tomodachi) is a compound of 友 (tomo, 'friend') and 達 (tachi, pluralizing suffix). The particle と (to) indicates accompaniment or association.
Usage Notes
The particle と is essential to convey the meaning of 'with' in this context. Omitting it would change the meaning entirely (e.g., 友達映画を見に行った would imply the friend is the movie, which is nonsensical).