〜ていく: Going On Doing & Changing From Now (Meaning + Examples)

The outward arrow it lays on the verb

On its own a verb just names an action. Bolt いく ("to go") onto its て-form and you overlay one extra idea: the action heads away from the speaker — in space or in time. That single overlay splits into two everyday jobs. First, it links two actions in sequence: you do something, then you go (食べていく = eat here, then leave). Second, with a verb of change it marks a trend that starts now and rolls forward into the future (増えていく = will keep increasing).

The thread tying both jobs together is movement away from "here and now." Keep that picture in mind and the pattern stays intuitive.

Which verbs it pairs with

Formation is simple: take the plain て-form of any verb and add いく. It conjugates as a normal verb (いく → いきます, いった, いかない), so the whole tense lives on いく, not on the first verb.

Which of the two jobs you get depends on the verb underneath. Action and motion verbs (持つ, 食べる, 走る, 連れる) give the "do it, then go" reading — 連れていく is "take a person along," 持っていく "take a thing along." Verbs of change (なる, 増える, 減る, 変わる, 続ける) give the "trend from now" reading, and pair naturally with これから ("from now"), だんだん, and どんどん ("gradually / steadily").

In casual speech ていく often shrinks to てく: 持ってく, 食べてく. You'll hear it constantly, so recognize it.

In use

With motion verbs, いく keeps its literal "go" sense — the て-form is the action you finish first, and いく is the departure that follows:

With a verb of change, the starting point is now and the arrow points at the future:

How it differs from its mirror, 〜てくる

This is the heart of the lesson. いく goes away; くる comes toward. That single difference flips the meaning of the whole phrase:

• 〜ていく = movement away from the speaker, or change from now into the future. 暑くなっていく = "it'll keep getting hotter (going forward)."
• 〜てくる = movement toward the speaker, or change up to now. 暑くなってきた = "it has been getting hotter (up to this point)."

So 持っていく is "take it (away from here)," while 持ってくる is "bring it (here)." And 増えていく looks ahead, while 増えてきた looks back at how things reached the present. Think of now as the dividing line: いく steps past it, くる arrives at it.

Two traps live right here. Pick your helper by where the thing ends up — 持っていく sends it away, 持ってくる brings it here. And never reach for ていく when the trend runs up to the present: "it's gotten hot lately" is 暑くなってきた, not 暑くなっていった. (Two smaller reminders: the tense always rides on いく — 食べていきました, never 食べましたいく — and not every 〜ていく is about the future; 歩いていく just means "go on foot.")

The short version

• 〜ていく = て-form + いく; tense lives on いく.
• Job 1: do an action, then go (持っていく = take along).
• Job 2: a change from now into the future (暑くなっていく).
• Core image: movement away from the here-and-now.
• Mirror it with 〜てくる (toward you / up to now).

Practice it