Japanese Ni vs To with Verbs: Au, Hanasu, Kekkon Suru and Niru

One-way and mutual: the idea behind ni and to

The clearest way to think about this pair is direction. Ni is an arrow: it points an action at a target, and the target does not have to do anything. To is a bracket: it puts two parties together, and both take part in the action. Some verbs can only be one-way, some only mutual, and the most useful ones can be either.

A quick test helps. Turn the sentence around and see whether it is still true. If Tanaka-san to kekkon shita is true, then Tanaka-san also married you, so to fits. If you tell Tanaka-san some news, Tanaka-san did not tell you the news back, so ni fits. When both directions are true at once, as with talking or meeting, Japanese lets you choose the particle that matches what you want to stress.

Au: meeting someone with ni or to

Au, to meet, is the verb that puzzles learners first, because both particles are common and correct. Hito ni au is the default. It treats the other person as the point you are heading for, which is why it pairs naturally with going somewhere: eki de tomodachi ni au, meet a friend at the station. It is also the only choice when meeting is one-sided, as in running into someone by chance, or seeing a doctor or a client.

Hito to au stresses that the two of you are meeting each other, usually by arrangement and with some time spent together. Kanojo to au sounds like a planned meeting between two willing parties; kanojo ni au is more neutral. The related verb deau, to come across, prefers to for people who meet by chance and become friends or partners, and ni for a thing or idea you happened upon.

Hanasu and sōdan suru: telling versus talking together

Hanasu covers both to tell and to talk, and the particle decides which. Tomodachi ni hanasu is to tell a friend something; the friend listens. It often takes a content object with o or a quoted clause with to: sono koto o tomodachi ni hanashita, I told my friend about that. Tomodachi to hanasu is to have a conversation; both people speak. The quoting to, I said that, is a different word, so one sentence can hold both: tomodachi ni ikanai to hanashita, I told my friend I would not go.

Sōdan suru, to consult, follows the same split. Sensei ni sōdan suru means you bring your problem to the teacher and the teacher advises you, the usual situation. Tomodachi to sōdan suru means you and your friend put your heads together over a shared problem. Iu, to say, setsumei suru, to explain, and oshieru, to tell or teach, are ni verbs, because the action is directed. Shaberu, to chat, leans towards to, because it describes an exchange.

Kekkon suru, niru and chigau: always symmetrical

Some relationships are the same from both sides. If A marries B, B marries A. If A resembles B, B resembles A. If A differs from B, B differs from A. Japanese marks all of these with to. Kekkon suru is the clearest case: Tanaka-san to kekkon shimashita is the only normal way to say I married Tanaka.

Niru, to resemble, uses to when the comparison is between equals: chichi to nite iru, I look like my father. Ni is also heard, chichi ni nite iru, and here the father is treated as the model that the child is measured against. Both are accepted; ni is a little more common in casual talk about family resemblance. Chigau, to differ, and onaji, the same, both pair with to, as do tsukiau, to go out with, kenka suru, to quarrel, and wakareru, to split up.

To issho ni and ni tsuite

To issho ni, together with, is the everyday way to say you did something in someone's company. The to already means with, and issho ni adds the picture of two people side by side doing the same thing. It is more common than bare to for going, eating, living and playing, and it lets you drop the partner when it is obvious: issho ni tabemasen ka, shall we eat together? Bare to is preferred with the mutual verbs above; to issho ni kekkon suru is odd, because marrying is already mutual.

Ni tsuite means about, concerning, and marks the topic of a verb of communication or thought: hanasu, kangaeru, kaku, shiraberu, kiku. Before a noun it needs no: Nihon no bunka ni tsuite no repōto, a report about Japanese culture. Both particles often appear in one sentence: tomodachi to shigoto ni tsuite hanashita, I talked with a friend about work.

Summary table: which particle each verb takes

The table gathers the verbs from this guide, with the standard particle, the possible alternative, and the change in meaning when both work.

Two rules cover most of the table. If the other person could be replaced by a place or a thing without changing the grammar, the verb takes ni. If the sentence remains true when you swap the two people around, the verb takes to.

Ni, to, e and de: keeping the neighbours apart

Because ni also marks destinations, learners sometimes swap it for e with these verbs. E marks a direction of movement and cannot mark a person you meet or talk to: tomodachi e au is wrong. De marks the place where an action happens, so it combines with any of these verbs without competing: kafe de tomodachi to hanasu, talk with a friend at a café. Most speakers say eki de tomodachi ni au, because the meeting happens at the station rather than the station being a destination.

• Ni: the person an action is aimed at (au, hanasu as tell, iu, sōdan suru, setsumei suru)
• To: the person who shares the action (kekkon suru, tsukiau, hanasu as talk, chigau, onaji)
• E: a direction of movement, never a person you meet or tell
• De: the place where the meeting or conversation happens
• Quoting to: marks what was said and sits right before iu, hanasu or omou

Common mistakes and how to fix them

The most frequent error is o with au: tomodachi o aimashita. English has a direct object after meet, but Japanese never does; use ni for a neutral meeting or to for a planned meet-up. The second is ni with kekkon suru, which sounds like an arranged marriage from a period drama; use to. The third is bare to where ni tsuite is needed: kaisha to hanashita means you talked with the company, not about it.

Politeness also interacts with the choice. With people above you, one-way verbs keep their ni: buchō ni sōdan suru, buchō ni hōkoku suru. Turning them into to versions does not make them more polite; it changes the meaning to a joint discussion, which can sound presumptuous.