The rentaikei conjugation (連体形) is the basic conjugation of verbs and verbal adjectives. This conjugation is also the form under which you would look for a word in a dictionary. It is therefore often referred to as the "dictionary form" or attributive form.

The rentaikei has two functions:
  1. The main (closing) verb of a sentence.
  2. The attributive verb in front of nouns.

The conjugation

The rentaikei conjugation of verbs can be recognized because it ends on a kana syllable from the "u" column. There is however one other conjugation which is used as the rentaikei: the ren'youkei +た (ta).

かうkauto buy
かくkakuto write
およぐoyoguto swim
落とおとすotosuto drop something
まつmatsuto wait
しぬshinuto die
すむsumuto live somewhere
食べたべるtaberuto eat

The rentaikei conjugation of verbal adjectives always ends on the "i"-syllable.

可愛い/かわいいkawaii/to be cute
い/たかいtakai/to be high / to be expensive
大きい/おおきいookii/to be large / to be big
小さい/ちいさいchiisai/to be small
楽しい/たのしいtanoshii/to be fun
少ない/すくないsukunai/to be little
Note: Not all adjectives ending on the "i"-syllable are verbal adjectives.
綺麗 (な)きれい (な)kirei (na)clean / pretty / beautiful
嫌い (な)きらい (な)kirai (na)a dislike

The main (closing) verb

In Japanese, the main verb is placed at the absolute end of the sentence. It may be followed by a particle, but that's about it. This verb is almost always in the rentaikei form.

手紙を書く。 (てがみをかく。)
Tegami wo kaku. I'm going to write a letter.

家が大きい。( いえがおおきい。)
Ie ga ookii. The house is big.

When dealing with a compound verb, the last part of the compound is in the rentaikei form.

来られる (こられる)
korareru (to be able to come)

来 (mizenkei of 来る "to come") +られる (rentaikei)

食べさせる (たべさせる)
tabesaseru (to have someone eat)

(mizenkei of 食べる "to eat") +させる (rentaikei)

書いている (かいている)
kaite iru (to be writing)

書いて (ren'yōkei + -te form of 書く "to write")
+いる (rentaikei of "to be")

買います (かいます)
kaimasu (to buy; polite)

買い (ren'yōkei of 買う "to buy") +ます (rentaikei
/ polite)

大きくない (おおきくない)
ōkikunai (to not be big)

大きく (mizenkei of 大きい "to be big") +ない (rentaikei/negative)

The rentaikei can function as both the main verb of the main clause and as the main verb of the subordinate clause. The two clauses must be connected by a conjunction such as "because" or "though".

The attributive verb

The rentaikei conjugation can also be used in front of nouns. In this case, the verb describes the noun it is placed directly in front of.

書く手紙 (かくてがみ)
kaku tegami (the letter I'm going to write)
買った物 (かったもの)
katta mono (the thing I bought)
大きい家 (おおきいいえ)
ōkii ie (the big house)

Rentaikei + ka (か)

明日、買います。
Ashita, kaimasu.
I'll buy it tomorrow.

明日、買います
Ashita, kaimasu ka.
Are you going to buy it tomorrow?

When using the informal form, か (ka) is often left out. Men may use it on occasion to sound tough, but women are preferred not to use it.

明日、買う?
Ashita, kau?
Are you going to buy it tomorrow?

明日、買うか。
Ashita, kau ka.
Are you going to buy it tomorrow, or what?

As you can see, when the particle "ka" is dropped, a question mark is placed at the end of the sentence. This is to be able to distinguish between a question and a statement. When "ka" is written no question mark is used.

When two sentences ending on the particle か (ka) follow each othe they are often combined in the translation with "or".

来ますか。来ませんか。
Kimasu ka. Kimasen ka.
Will you, or won't you be coming over?

買うか。売るか。
Kau ka. Uru ka.
Will you be buying or selling?

Rentaikei + かどうか (ka dou ka)

This construction is used for combining a positive question and it's negative counterpart in one.

高かったかどうか。
Takakatta ka dou ka.
Was it expensive or wasn't it?

行けますかどうか。
Ikemasu ka dou ka.
Will you be able to go or not?.

Rentaikei + かな (ka na) or かなあ (ka naa)

This is a simple dubitative. It illustrates a certain amount of doubt you have concerning the statement you just made. かなあ (ka naa) conveys a larger amount of doubt than かな (ka na).

仙台に行けるかな。
Sendai ni ikeru ka na.
I wonder if I can go to Sendai.

兄ちゃんが買い物しましたかなあ。
Nii-chan ga kaimono shimashita ka naa.
I doubt that my brother did the groceries.

Rentaikei + かも知れない (ka mo shirenai)

The combination "ka mo shirenai" or "ka mo shiremasen" means "maybe" or "perhaps". In speech often abbreviated to "ka mo".

行くかも知れません。
Iku ka mo shiremasen.
Maybe I'll go.
買うかも知れない。
Kau ka mo shirenai.
I might buy it.
高くないかも。
Takakunai ka mo.
Perhaps it's not expensive.

Note: In combination with "ka mo shirenai" the preceding verb cannot be in the polite form. Also, the contracted verb だ (da) is dropped before the particle か (ka):

行きますかも知れません。Ikimasu ka mo shiremasen. (incorrect!)
高いですかも知れない。
Takai desu ka mo shirenai. (incorrect!)
大阪だかも。
Osaka da ka mo. (incorrect!)

Rentaikei + かしら (ka shira)

かしら (ka shira) means "I wonder if" or "maybe". "Ka shira" is the femine form of "ka mo shirenai" and describes a greater amount of doubt than "ka mo shirenai" does.

行くかしら。
Iku ka shira.
I wonder if I'll go.
買うかしら。
Kau ka shira.
Maybe I'll buy it.
高くないかしら。
Takakunai ka shira.
It might not be expensive.

Note: In combination with "ka shira" the preceding verb cannot be in the polite form. Also the contracted verb だ (da) is dropped before the particle か (ka).

行きますかしら。
Ikimasu ka shira. (incorrect!)
高いですかしら。
Takai desu ka shira. (incorrect!)
大阪だかしら。
Osaka da ka shira. (incorrect!)

There is no polite form for "ka shira." For situations where politeness is required you should use "ka mo shiremasen."

Rentaikei + sou (そう)

The rentaikei + そう (sou) is used to describe "hearsay". It is only used for information you got from a third party. It is often followed by a form of "de aru" (da/desu).

雨が降るそうです。
Ame ga furu sou desu.
I heard it's going to rain.

地下鉄が高いそうだ。
Chikatetsu ga takai sou da.
I heard the subway is expensive./p>

日本製だそうだ。
Nihonsei da sou da.
I heard it's Japanese-made.

Note: The verb preceding "sou" cannot be in the polite form. To make the sentence polite, the main or closing verb should be in the polite form.

雨が降りますそうです。 (Ame ga furimasu sou desu.) (incorrect!)

Rentaikei + to (と)

The rentaikei + と (to) is one of several conditional forms. It is often used to describe an assumption, translated as "if" or "when", usually referring to recurring situations. It cannot, however, be used for describing requests, permission, wishes or recommendations.

The rentaikei + と (to) can also be used to describe an observation or conclusion. In this case it can be translated as "Now that I…" (often encountered as ren'youkei + てみると (te miru to)), as "when" or "while", describing a coincidence or one-off occurrence (used as とき (toki)), or as "and then" when actions are performed by the same grammatical subject.

The rentaikei + と is never found at the end of a sentence. It always ends the conditional clause, followed by the main clause.

安いとぜひ買った。
Yasui to zehi katta.
If it were cheap I would definitely have bought it.

田中さんが着くとパーティが始まります。
Tanaka-san ga tsuku to paati ga hajimarimasu.
The party will start when Mr. Tanaka gets here.

そのようなことが言われるといやだ。
Sono you na koto ga iwareru to iya datta.
I hate it when I'm being told something like that.

Note: The verb before the conditional "to" cannot be in the past tense.

安かったと買った。
Yasukatta to katta. (incorrect!)
着いたと始まります。
Tsuita to hajimarimasu. (incorrect!)
言われたといやだ。
Iwareta to iya da. (incorrect!)

Rentaikei + と・・・言う (to iu)

This use of the particle to is known as the "citing と (to)". It can be used, not only with と言う (to iu), but with any verb that is capable of citing or quoting to create direct or indirect speech. The "to" in this case doesn't belong with the rentaikei but with the citing or quoting verb.

と言う (という)
to iu (say)

と考える (とかんがえる)
to kangaeru (think)

と感じる (とかんじる)
to kanjiru (feel)

と聞く (ときく)
to kiku (hear)

と知る (としる
to shiru (know)

と呼ぶ とよぶ
to yobu call / name

と分かる とわかる
to wakaru understand

田中さんがしたと山本さんが言った。
Tanaka-san ga shita to Yamamoto-san ga itta.
Mr. Yamamoto said that Mr. Tanaka did it.

「田中さんがした。」と山本さんが言った。
"Tanaka-san ga shita." to Yamamoto-san ga itta.
" Mr. Tanaka did it." said Mr. Yamamoto.

熊本君は新しい彼女ができたと聞いた。
Yamamoto-kun wa atarashii kanojo ga dekita to kiita.
I heard that Kumamoto has a new girlfriend.

黒いと知っています。
Kuroi to shitte imasu.
I know it's black.

私が馬鹿だとみんなに呼ばれた。
Watashi ga baka da to minna ni yobareta.
I was called a fool by everyone.

そうだと分かります。
Sou da to wakarimasu.
I know (understand) it's like that.

Note: The verb before the citing "to" can only be in the polite form if it is direct speech, this does not make the sentence polite though. The sentence can be made polite by making the citing or quoting verb polite.

黒いですと知っています。
Kuroi desu to shitte imasu. (incorrect!)
日本に行きますと聞いた。
Nihon ni ikimasu to kiita. (incorrect!)
いやですと言われました。
Iya desu to iwaremashita. (incorrect!)
「いやです。」と言われました。
"Iya desu." to iwaremashita.
"I don't like that." I was told.

Rentaikei + と言うと (to iu to)

The rentaikei + と言うと (to iu to) is translated as "meaning". Literally, it means "when you say".

明日と言うと日曜日ですね。
Ashita to iu to nichiyoubi desu ne.
Tomorrow, meaning Sunday, right?

Rentaikei + とならない (to naranai) / + といけない (to ikenai)

Special combinations with と are the rentaikei + とならない (to naranai) or the rentaikei + といけない (to ikenai). These combinations form a prohibitive, and are translated as "mustn't". When using the double negatives mizenkei + ないとならない (nai to naranai) or mizenkei + ないと行けない (nai to ikenai) these combinations form an imperative, and are translated as "must" or "have to".

行くとならない
Iku to naranai.
You cannot go. / You may not go.

行かないとならない
Ikanai to naranai.
You have to go. / You must go.

行くといけない
Iku to ikenai.
You cannot go. / You may not go.

行かないといけない
Ikanai to ikenai.
You have to go. / You must go.

Rentaikei + na (な)

The rentaikei + な (na) is a prohibitive form. In other words, you use this form to tell someone that they must not do anything.

飲むな。
Nomu na.
Don't drink!
乗るな。
Noru na.
Don't drive!
渡るな。
Wataru na.
Don't cross (the road)!

This is a very firm order, there are more subtle ways to persuade people not to do something.

Note: This form can be made more polite by using honorific verbs instead of the regular verbs. The ます (masu) form can also be used but is not as common.

Note: Be careful not to confuse "rentaikei + な" with "ren'yōkei + な".

飲むな。
Nomu na.
Don't drink!
飲みな。
Nomi na.
Drink!

Rentaikei + nara (なら) / naraba (ならば)

The rentaikei + なら (nara) is one of several conditional forms. It should be translated as "if" or "when". There's no fundamental difference between "nara" and "naraba". At the most "naraba" sounds a little more formal than "nara".

なら (nara) can also be used after nouns. Another possible combination is "rentaikei + のなら (no nara)".

The rentaikei + なら is never found at the end of a sentence. It always ends the conditional clause, followed by the main clause.

なら (nara), unlike some other conditional forms, cannot be used as a temporal form. なら (nara) and ならば (naraba) are strictly used as conditional forms.

そうするならできない。
Sou suru nara dekinai.
If you do it like that it won't work.

明日ならば行けます。
Ashita naraba ikemasu.
If it's tomorrow, I can go.

貴方がしないのなら誰がするでしょうか。
Anata ga shinai no nara dare ga suru deshou ka.
If you don't do it, who will?

飲むなら乗るな。乗るなら飲むな。
Nomu nara noru na. Noru nara nomu na.
If you drink, don't drive. If you drive, don't drink.

Note: "nara" cannot be preceded by any form of "de aru" (da / desu). This verb will then be dropped.

車だなら運転できない。
Kuruma da nara unten dekinai. (incorrect!)
命令ですならしません。
Meirei desu nara shimasen. (incorrect!)
明日であるなら行ける。
Ashita de aru nara ikeru. (incorrect!)

Rentaikei + no (の)

The rentaikei + の (no) substantivates the verb, or in other words, turns the verb into a noun. It has the same function as 事 (koto) meaning "thing" or "matter".

今、読むのは本だ。
Ima, yomu no wa hon da.
What I'm reading at the moment, is a book.

Since the verb has now become a noun, you can use it as the grammatical object, subject or indirect object if you wish. This results in combinations with the particle の (no) and other particles.

買いたいのが高い。
Kaitai no ga takai.
The one I want to buy is expensive.

高いのを買わない。
Takai no wo kawanai.
I'm not going to buy the expensive one.

聞いたのは鳥です。
Kiita no wa tori desu.
What I heard was a bird.

小さいのにあります。
Chiisai no ni arimasu.
It's in the small one.

速いので行ってみたい。
Hayai no de itte mitai.
I want to try and go with the fast one.

Note: besides "no ni" and "no de" you may also encounter "noni" and "node". Their functions are quite different.

Rentaikei + のだ (no da)

The rentaikei + のだ (no da) gives the main verb some emphasis, but in translations, it's usually left out. The "no da" construction is often used to put some variation in one's writing or speaking style to make it less monotonous.

明日、行くのです。
Ashita, iku no desu.
I'm going tomorrow. (literally: It's that I'm going tomorrow.)

新しい車が高いのだ。
Atarashii kuruma ga takai no da.
New cars are expensive. (literally: It's that new cars are expensive.)

Rentaikei + の? (no?)

The rentaikei + の? (no?) is short for のだか。 (no da ka.). The function is the same as the rentaikei + か (ka) except that it is only used in informal speech. In combination with polite forms, か should be used.

明日、行くの?
Ashita, iku no?
Are you going tomorrow?

新しい車が高いの?
Atarashii kuruma ga takai no?
Are new cars expensive?

Note: verbs preceding の (no) cannot be in the polite form. These are incorrect or have a different meaning.

聞きましたのです。
Kikimashita no desu. (incorrect!)
高いですの?
Takai desu no? (incorrect!)
速いですので行ってみたいです。
Hayai desu no de itte mitai desu. (incorrect!)
速いですので行ってみたいです。
Hayai desu node itte mitai desu.
I want to try and go there because it's fast.

Rentaikei + beki (べき)

The rentaikei + べき (beki) is an imperative, but constitutes more of strong advice rather than an order or inevitability. The rentaikei + べき (beki) can often be translated as "you should" or "you ought to".

A common contraction occurs when べき (beki) is combined with the verb する (suru) meaning "to do". Both するべき (suru beki) and すべき (subeki) can be used.

べき (beki) is always followed by a form of "de aru" (da / desu).

暴力に訴えるべきではない。
Bōryoku ni uttaeru beki de wa nai.
You must not resort to violence.

勉強するべきでした。
Benkyō suru beki deshita.
I should have studied.

勉強すべきでした。
Benkyō subeki deshita.
I should have studied.

Rentaikei + mai (まい)

The rentaikei + まい (mai) is the negative form of the subjunctive form. まい (mai) is placed after the main (or closing) verb, also when that closing verb is in the polite form, but cannot be combined with verbal adjectives.

Group 2 verbs are often contracted or abbreviated by removing the final る (ru).

彼を待つまい。
Kare wo matsumai.
I don't think they'll wait for him. / They probably won't wait for him.

この先はまあ話しますまい。
Kono saki wa maa hanashimasumai.
I'd rather not tell you the rest.

彼を待つまい。
Kare wo matsumai.
I don't think they'll wait for him. / They probably won't wait for him.

あれはできるまい。
Are wa dekirumai.
I don't think that's possible. / That probably won't be possible.

食べ物ではあるまい。
Tabemono de wa arumai.
I don't think that's food.

子供じゃあるまいし、それぐらい分かってるよ。
Kodomo ja arumai shi, sore gurai wakatteru yo.
I'm quite aware of that, thank you very much. I'm not a child, you know!

Note: When combining まい (mai) with である (de aru), you should insert the particle は (wa) like in ではない (de wa nai), since まい (mai) also is a negative form.

Rentaikei + mitai (みたい)

The rentaikei + みたい(な) (mitai na) is one of several ways to say "similar to" or "seem that". It is often followed by a form of "de aru" (da / desu).

When combined with a verb, みたい(な) (mitai na) describes an impression you have. When combined with a noun, みたい(な) describes a resemblance.

雨が降るみたいです。
Ame ga furu mitai desu.
It appears to be raining.

新しいみたいだ。
Atarashii mitai da.
It seems new.

子供みたいな事をしました。
Kodomo mitai na koto wo shimashita.
He did something childish.

子供みたいに遊んだ。
Kodomo mitai ni asonda.
They played as though they were children.

みたい(な) (mitai na) is never placed after だ (da). When using みたい(な), だ is dropped.

子供だ。
Kodomo da.
They are children.

子供みたいだ。
Kodomo mitai da.
They are like children.

Note: The verb preceding "mitai" cannot be in the polite form. To make the sentence polite, the main or closing verb should be in the polite form.

雨が降りますみたいです。
Ame ga furimasu mitai desu. (incorrect!)
日本人だみたいだ。
Nihonjin da mitai da. (incorrect!)

Note: みたい (mitai) is a "na-nominal" or non-conjugated adjective. To find out more about conjugated and non-conjugated adjectives check the adjectives page.

Note: do not confuse みたい(な) (mitai na), which means "resembling", with 見たい (mitai), which means "to want to see".

Rentaikei + rashii (らしい)

Rentaikei + らしい (rashii) means "to seem" or "to be like". らしい (rashii) is a verbal adjective and can be conjugated like any other verbal adjective. For more information on conjugated and non-conjugated adjectives check the adjectives page.

らしい (rashii) can also be placed directly after nouns. In these cases it should be translated as "it's typically" or "it's just like".

雨が降るらしい。
Ame ga furu rashii.
It appears to be raining.

日本人らしいです。
Nihonjin rashii desu.
That's typically Japanese.

彼が来ないらしいです。
Kare ga konai rashii desu.
It seems like he's not coming.

田中さんらしくない。
Tanaka-san rashikunai.
That's not like Mr. Tanaka (to do something like that).

日本人らしい日本人です。
Nihonjin rashii nihonjin desu.
She's Japanese through and through.

らしい (rashii) is never placed after だ (da). When using らしい, だ is dropped.

女だ。 (Onna da.)
It's a woman.

女らしい。
Onna rashii.
That's just like a woman. / It's typically feminine.

Note: The verb preceding "rashii" cannot be in the polite form. To make the sentence polite, you can add "desu" after らしい (rashii) if らしい is the closing verb, else the closing verb should be made polite.

雨が降りますらしいです。
Ame ga furimasu rashii desu. (incorrect!)
日本人だらしい。
Nihonjin da rashii. (incorrect!)
日本人らしいです日本人です。
Nihonjin rashii desu nihonjin desu. (incorrect!)

Rentaikei + you (よう)

The rentaikei + よう(な) (you na) is one of several ways to say "similar to" or "seem that". It is often followed by a form of "de aru" (da / desu). よう (you) can also be written with the kanji 様 (you).

When combined with a verb, よう(な) (you na) describes an impression you have. When combined with a noun, のよう(な) describes a resemblance. The particle の (no) must be used when combining よう(な) with a noun.

雨が降るようです。
Ame ga furu you desu.

It appears to be raining.

新しいようだ。
Atarashii you da.
It seems new.

子供のような事をしました。
Kodomo no you na koto wo shimashita.
He did something childish.

子供のように遊んだ。
Kodomo no you ni asonda.
They played as though they were children.

よう(な) (you na) is never placed after だ (da). When using よう(な), だ is changed for の (no).

子供だ。
Kodomo da.
They are children.

子供の様だ。
Kodomo no you da.
They are like children.

Note:The verb preceding "you" cannot be in the polite form. To make the sentence polite, the main or closing verb should be in the polite form.

雨が降りますようです。
Ame ga furimasu you desu. (incorrect!)
日本人だようだ。
Nihonjin da you da. (incorrect!)
日本人ようだ。
Nihonjin you da. (incorrect!)

Note:よう (you) is a "na-nominal" or non-conjugated adjective. To find out more about conjugated and non-conjugated adjectives check the adjectives page.

Note:do not confuse the rentaikei + よう(な) (you na) with the mizenkei + よう (you).

References: