BACK TO HOMEPAGE QUICK AND DIRTY GUIDE TO JAPANESE GRAMMAR
The following is a verbatim copy of a Usenet posting by Tad Perry from 1992 which is on the Internet in various forms. I have taken the liberty of re-arranging it slightly with the assistance of html.

SENTENCES

WORD ORDER

Before talking about particles let's get into word order. In general, standard word order for Japanese when using an action verb is:

[SUBJECT]+TIME+PLACE/IMPLEMENT
    +INDIRECT OBJECT+OBJECT+ACTION VERB

    "Ashita, gakkou de sensei ni purezento wo agemasu."
    [I'm] going to give a present to [my] teacher tomorrow.
 

For an existence verb it is:

[SUBJECT]+TIME+LOCATION+EXISTENCE VERB

    "Takahashi wa, ima honsha ni iru."
    Takahasi is in the main office right now.
 

For a motion verb it is:

[SUBJECT]+TIME+ORIGIN+ROUTE+DESTINATION+MOTION VERB

    "Ashita, paatii ni iku."
    I'm going to a party tomorrow.
 
 

SUBJECTS
are put in brackets to stress that they are very often deleted. In general, if a new subject is introduced where another had been previously understood, signal the change by placing "wa" after the subject. If a subject is understood, but for some reason not deleted (that's rare) use "ga" or nothing. Often you can move a subject out after the verb when things start piling up before the verb. Like:

    "Ashita boku ga kooen de utau."
    I'm singing at the park tomorrow.

often becomes:

    "Ashita kooen de utau, boku."

For more on SUBJECTs, see the longer description in the next section, "Subjects and Deletion". Knowing how to delete is a key to sounding natural.
 

TIME
is usually followed by "ni". In general, use "ni" for specific points in time or specific spans of time. So "jyuu gatsu [ni]" (October), "san gatsu mikka [ni]" (March 3rd) take "ni".
    A word like "ashita" (tomorrow) can only be understood by context (it changes depending on when you say it). These types of words are called "deictic" time words and don't take "ni".
    "Ashita iku" ("I'm going tomorrow."),
but:
    "sanji ni iku" ("I'm going at 3.")

Even if you have trouble making the distinction between these two types of time words, don't worry: Japanese people can understand what you mean even if you get it backwards.
 

PLACE/IMPLEMENT
is followed by "de". By PLACE, I mean the location that a volitional action occurred. If you're eating at home, that's "ouchi de shokuji suru". If you're eating with chopsticks, that's "ohashi de taberu". The place you do something or the thing you use to do something takes "de". If you're going somewhere by car, you say "kuruma de iku". It's not that hard to understand, really.

See INDIRECT OBJECT for why DESTINATIONs are different. Verbs of motion that tell DESTINATION, or ones of existence that tell the LOCATION of something take "ni". (DESTINATIONs can also take "he".)

Try to distinguish PLACE from LOCATION by thinking of it this way:
    PLACE is WHERE SOMETHING IS DONE,
    LOCATION is WHERE SOMETHING OR SOMEONE IS.
 

Use "kara" ("from") after an ORIGIN and "wo" after a ROUTE.

    "Gakkoo kara, kooen wo totte, ouchi ni kaeru."
    ("I'm going home from school through the park.")

There's usually an intermediate verb in this type of usage.
 

OBJECT
is followed by "wo" or nothing.

    "Hon wo yonde iru."
    (I'm reading a book.)

This is a really simple one in most cases. I really don't know many Japanese learners who can't understand this.
 

INDIRECT OBJECT
is followed by "ni". By INDIRECT OBJECT, I mean a sort of secondary object that some verbs take.

    "Kono hon wo anata ni ageru."
    ("I'm going to give this book to you.")

You have "this book" and you have "to you". The "this book" part is the OBJECT. The "to you" part is the INDIRECT OBJECT. "Wo" and "ni" are used to distinguish these two.
 

VERB
doesn't take any particles, but it needs to be inflected. There's a big section at the end on how you do that, and useful colloquial English equivalents of what those inflections mean. To boil this section down, remember it this way:

SUBJECT+wa/ga/nothing (delete subject if possible, show changes with "wa") TIME+ni/nothing (use nothing if it's a deictic time word) PLACE/IMPLEMENT+de (is the place where you do or where you are) LOCATION+ni (is the place where you *are* or where you *do*?) ORIGIN+kara ROUTE+wo (is this a place on the way to where you're going?) DESTINATION+ni/he (use "ni" over "he" but be aware that both are okay.) INDIRECT OBJECT+ni (use this if you're out of choices :-)
DIRECT OBJECT+wo

After understanding the descriptions given earlier, these nine lines are the key to knowing what particle to use 90% of the time. Even if these rules cause you to make a mistake you're definitely being understood.
 

Subjects and Deletions
Usually, you don't have to worry about whether to use wa or ga, because most subjects can usually be deleted. "You can't get something wrong, if you left it out in the first place." That's my philosophy. So we'll work on the parts of sentences that you can delete, starting with subjects.

    If you turn to a Japanese and suddenly make a statement:
    "Ashita paatii ni iku."
    ("[I'm] going to the party tomorrow.")
the listener will assume the subject is you. So don't bother supplying any subject. To do so, is in fact, not natural; a Japanese wouldn't normally do it.

    If you turn to a Japanese and suddenly ask a question:
    "Ashita paatii ni iku?"
    ("[Are you] going to the party tomorrow?")
the listener will assume the subject is himself or herself. Easy! Most one-on-one conversations where you or the listener is the subject don't need an explicit subject. No chance of screwing up wa/ga here.

    If you suddenly turn to a Japanese and want to make a statement or ask a question about some other person altogether, use "wa" after that person's name or title the first time you mention that person:
    "Shachoo wa, ashita paatii ni iku?"
    ("Is the shachoo going to the party tomorrow?")
Let's just say the "wa" introduces a change in subject. This time it signals a change from the default "you the listener" to the "shachoo".

    After you establish that you're talking about the president, you can go back to dropping subjects again:
    "Sono ato wa, kaeru ka na?"
    "Is he going home after that?"
--again some vagueness added with "ka na" ("I wonder"). Don't be too forward making assumptions about other people. This trick also stops the listener from thinking the question is back to being about himself. There's a strong tendency for questions to erase understood info and you have to signal that things are unchanged. Usually you play with the verb a little bit to get this across. Note that the change in time being talked about was also signaled with a "wa".) Note that this tendency to delete in Japanese parallels the point where an English native speaker would use plain pronouns like, I, you, he, she, they. When you start a comment about yourself, you use "I" (Japanese delete). When you ask about the listener, you use "you" (Japanese delete). When you've first established someone and then keep going with that person, you use "he" or "she" (Japanese delete). See? Simple.

Deleting other Established Info
Just like with subjects, any info that's been established can be deleted, and any changes in established info can be signalled using "wa":

    "Ashita paatii ni iku?"
    ("[Are you] going to the party tomorrow?")

    "Un, anata wa?"
    ("Yeah, how about you?")
--info about "paatii ni" and "iku" unchanged, therefore deleted. Subject changed to original questioner, so the change is signaled with "wa".

    "Un-n, ikanai"
    ("No, I'm not going.")

--info about "paatii ni" still deleted, "iku" comes back as "ikanai" because it has changed form.

    "Sono ato no eiga wa?"
    "How about the movie afterwards?"
--the established info "paatii" changed to "eiga" so we use "wa" to establish the change in understood information. Understood info that *hasn't* changed is still left out, like the subject "boku" and the action "iku".)

    "Un-n, ikanai."

This is pretty much how deletions work whether it be subjects or something else. In general, always go for deletions if possible. This section also serves the purpose of giving you a feel for "wa".
 

Particle Ga
In general, you don't need it. In the instances where you do, you can slowly build a feel for it. Basically, you need it in situations where you're not expressing a change in subject, but where you want to state the subject even though it is established info. Usually, this is to add emphasis or avoid ambiguity.

    "Shacho wa, ashita paatii ni iku?"
    ("Is the shachoo going to the party tomorrow?")

    "Un-n, ikanai mitai."
    ("No, it doesn't look like it.")

--throw in a "mitai" because you don't wan't to act too sure of the actions of others in Japanese. We're not really covering that though, it's just a side note.

    "Nande?"
    ("Why not?")

    "Sore ga wakaranai."
    ("I don't know why not.")

--there's no real ambiguity in this case, and "wakaranai" alone would have worked, but it is a case where you're not changing an understood subject to another, you're restating the understood subject as such for some emphasis. If you're stating an established subject, for whatever reason, use "ga". But you could've deleted, and if you were following my explanation you should have. This one sentence also helps dispell the huge MYTH that "wa" is for negative sentences.
 

Particle Mo
Use mo when you're adding more info on a list of established info. It may be used alone when marking subjects and objects, and can follow other particles (like ni, de, and he). Put it this way: if "wa" clears the understood info and replaces it, "mo" adds extra info on top of what's already there without clearing out anything.

    "Ashita paatii ni iku?"
    ("[Are you] going to the party tomorrow?")

    "Un, iku yo."
    ("Yeah, I'm going, how about you?"
    --note what was deleted and why.)

    "Boku mo iku."
    ("I'm going too."
    --add yourself to the understood subject.)

Mo is easy, so we won't waste any more time with it. Just trying to be complete and it only took a few lines to do.
 

INTRO to GUIDE

-RU VERBS (GROUP II)

-U VERBS (GROUP I)

IRREGULAR VERBS

ADJECTIVES

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