～ていく・～てくる

How it works

いく (go) and くる (come) attached to a て-form keep their sense of direction, but the reference point is always the speaker, here and now. Three uses overlap:

1. Do, then move. 買ってくる = buy it and come back here; 持っていく = take it along as you go. 行ってきます literally means “I go and come back”, which is why it is what you say when leaving home.
2. Movement with manner. 走ってくる (come running), 飛んでいく (fly away), 歩いていく (go on foot). The て-verb describes how the moving happens.
3. Change in time. With verbs of change (なる, 増える, 減る, 分かる), ～てくる says the change has been building up to the present, 寒くなってきた (it has got cold), and ～ていく says it will keep going from now on, 寒くなっていく (it will keep getting colder).

The auxiliary is usually written in kana (なってきた, 続けていく); 持って行く／持って来る with kanji are also common when real movement is meant. Conjugate the final verb as usual: 買ってきます, 買ってきた, 持っていって, 持っていかない. Remember that 来る is irregular: きます, きた, こない.

Examples

• 近くの店でお弁当を買ってきます。（ちかく の みせ で おべんとう を かって きます）— I’ll go and buy a bento at the shop nearby.
• 傘を持っていったほうがいいですよ。（かさ を もって いった ほう が いい です よ）— You’d better take an umbrella with you.
• 最近、だんだん寒くなってきましたね。（さいきん、だんだん さむく なって きました ね）— It’s been getting colder lately, hasn’t it?
• これからも日本語の勉強を続けていきます。（これから も にほんご の べんきょう を つづけて いきます）— I’ll keep on studying Japanese from now on.
• 鳥が空へ飛んでいった。（とり が そら へ とんで いった）— The bird flew off into the sky.
• 友達が駅まで走ってきた。（ともだち が えき まで はしって きた）— My friend came running all the way to the station.

Compare with

買いに行く vs 買ってくる

買いに行く only states the purpose of a trip. 買ってくる bundles the errand with the return, so it is the natural thing to announce when you will be right back: ちょっとパンを買ってくる.

～ている vs ～てきた

寒くなっている describes the state now (it is cold). 寒くなってきた describes the change arriving at the present (it has been turning cold). For a change still on its way into the future, 寒くなっていく.

～たばかり

着いたばかりだ means you arrived only a moment ago. 着いてきた is not recent past and is not natural Japanese at all: after a movement verb, ～てくる says the movement is how you got here (走ってきた, 歩いてきた), which makes no sense with 着く.

Traps for Spanish, English and French speakers

• Spanish ir a + infinitive and French aller + infinitive are future tenses, so learners produce ✗ 明日は映画を見ていきます for “voy a ver una película”, which a Japanese listener hears as “I’ll watch a film and then leave”. ～ていく is not a future marker; say ✓ 明日は映画を見ます or 見るつもりです.
• French venir de + infinitive (recent past) is not ～てくる: ✗ 今着いてきた for “je viens d’arriver”. Use ✓ 今着いたばかりです; after a movement verb ～てくる describes how you got here (走ってきた, 歩いてきた), so 着いてきた is simply not Japanese.
• Spanish llevar／traer and English take／bring cover both objects and people, so learners write ✗ 友達を持ってきました or ✗ 子どもを持っていく. Japanese splits them: objects take 持っていく／持ってくる (✓ 傘を持っていく), people and animals take 連れていく／連れてくる (✓ 友達を連れてきました). French speakers already make this split with apporter／amener.
• English speakers read 雨が降ってきた as “the rain came” and 分かってきた as “I understood and came”. With change verbs ～てくる means the change has reached the present: “it has started raining”, “I’m starting to understand”; ～ていく (暖かくなっていく) projects the change into the future.