Japanese Grammar FAQ
I began writing this FAQ when I was still at a relatively early stage of learning Japanese. A fair few years must have past... so now I intend to write this thing up from start to finish.
For the most part, I'll be referencing grammar questions that arose in the thejapanesepage.com 's forums. Any recommendations or personal queries? Feel free to send me a PM. I want to arrange these grammar questions starting with general/common questions, and gradually getting more specific and uncommon. I will try and answer them as concisely as possible. Anyone is welcome to make improvements (or corrections!) but I appreciate your asking first.
That said, Yoroshiku!
だ(da) VS です(desu)
The copula だ・です is used to finalize a statement. They mean the same thing, except that です is polite and, like any polite Japanese, is usually prioritized when speaking to anyone outside of friends and family. The extremely polite form is でございます (de gozaimasu)
Other forms of this word include である (de aru) which is used in formal or academic text/speech. It sounds very certain and sometimes even proud - like the title of Natsume Soseki's book: 我輩は猫である "I am a Cat." The Samurai-esque alternative is でござる (de gozaru).
Can I use か(ka) after だ(da)?
When asking a question in polite Japanese, your sentence will often end in 「ですか。」However, even though ですis a polite form of だ, Japanese people do not say だか, which actually gives off a distinct country-bumpkin feel. Questions in casual speech are best ended with the particle の (refer to the んだ・のだ section)
It should also be noted that だ should not follow an i-adjective （「い形容詞」）or a verb.
寒いだね X 寒いね ０
さむいだね X さむいね ０
On the other hand, verbs/i-adjectives can be joined to だ with ん/の but the meaning will be affected. For example:
The first sentence means "It's (or "I'm") cold." The second sentence could mean "Oh it's cold" (contrary to my expectation) or "I'm cold" (in explanation.) Please refer to the んだ・のだ section for more details.
What is ～んだ (-nda) / What is ～のだ (-noda)
～んだ is a contraction of ～のだ. They are interchangeable, and both can be used in polite or casual Japanese. Since the former is more common, using the latter will sound like you are purposefully trying to sound serious, or proper, so I would say it works well in polite Japanese.
They can follow an い形容詞 (i-adjective) or a verb. If you want to follow a な形容詞(na-adjective) you must include the な(na), please see examples below. Usage should be covered elsewhere, but I'll just say that inserting ん or の suggests one is seeking an explanation (when used in a question) or giving an explanation (when used in a statement.)
Using ん・の in a question:
イギリスは、今寒くないんですか Isn't the UK cold now? (Here「ん」demonstrates the speakers interest for the listener's knowledge/explanation.)
宿題はもうやったの？ Have you already done your homework? (In casual speech, it generally works well to use の as your question marker.)
Using ん・の in a statement can be to give an explanation, or acknowledge/understand something you didn't before.
これは、便利なのです。 This useful/convenient. (Here the「の」is saying 'that's why!' in explanation as to why you like or recommend something.)
終わったんだ。 It's finished/over (Here ん describes the speaker's realization at that very moment that something has finished.)
Conditionals: what's the difference?
In English, we use the word "if" a lot; some of our conditionals ("were I to.." "should you..") are falling out of use. By contrast, Japanese has a number of conditionals that are all used frequently, and understanding the way to distinguish the use of these is a challenge all Japanese learners will face. Despite having distinct nuances, there are times when more than one conditional will fit a given sentence, which is probably one of the causes of confusion.
と is placed after a verb in dictionary/plain form. For example, 見ると (if/when I look.) Whatever follows next, と tells us that it follows (or followed) succinctly, smoothly, directly. This can be thought of as 'cause and effect.' 写真を見ると、彼を思い出します。When I look at the photo, I remember him. しゃしんをみると、かれをおもいだします。
It is often used in the context of giving advice. In such a context, it is clearly more assertive than ば or たら。
それを持っていくと便利ですよ If you take that with you, it's useful! (underlying nuance: you really ought to take it!)
暖かいうちに食べるといい It's better if you eat it whilst it's hot (underlying nuance: I really recommend you eat it whilst it's hot)
- Advanced: と following the volitional form of a verb will create the meaning 'even if' (usually expressed with verb stem + ても) I feel that using と in this way has a sense of poetry or emotion.
何を言われても、気にしない ＞＞＞ 何を言われようと、気にしない
Has the nuance of 'provided that.' 'On condition that.' なら directly follows a verb or noun.
あなたも行くなら、私も行く If you will go, I will go too. (underlying nuance: I'll go too but only if you are)
君ならできる If it's you, you can do it (underlying nuance: If anyone can do it, you can)
ている VS てる
Leaving out the い does not change the meaning, てる originated from fast colloquial speech patterns (in the same way as people say 'gonna' for 'going.'
汗をかいている ＞＞＞ 汗をかいてる