Can someone help me understand Japanese particles?

Question

This my first post, so hello everyone!

1. wa vs ga: When I introduce myself to someone, is it always assumed that my name is already the topic even though nobody has mentioned it before? I've never heard anyone say "boku no namae ga". We always say "wa". Also, what happens if I am already talking about a topic, but provide completely new and astounding information about it, e.g, I spend an hour talking about my dog to my friend and then I suddenly tell him: "my dog can fly"? Ignoring the absurdity of the statement, would I use ga or wa here?

2. Does the subject always need to be a specific word, e.g, if I am talking about food do I still need to use "ga" for every new food that I mention?

3. o vs wa: For example, when do I use "gohan o tabe masu," and when do I need "gohan wa tabe masu." Gohan may be the topic but it is also the object of an action. Is it interchangeable in this case?

Answer 1

For questions about when you can and cannot use は, I generally find a good rule of thumb is to try translating any "(something) + は" to "as for (something)" or "regarding (something)" in English, and see how it sounds:

私{わたし}の名前{なまえ}はジョンです
As for my name, (it) is John.

Just as with は, "as for ___" has similar implications about bringing up some subject that's already being discussed or already in the listeners' mind as a possible topic for discussion (the "universe of discourse"). In the above case, "as for" doesn't seem too out of place, and thus we can probably use は, because my existence is already part of the conversation (I would hope) and it's assumed that everybody has a name, so the concept of my name is something that's already present in the potential realm of our discussion, and (particularly in Japanese), anyone who doesn't know my name is probably already wondering to themselves what it is, so it's going to be on their mind already.

On the other hand, if I were to say (out of the blue) "As for my dog, he likes to run around", your reaction might be more of "wait, what do you mean 'as for' your dog? Were we talking about that before and I missed it?". This is a case where が is the more appropriate particle, because "my dog" isn't something that's already potentially on people's minds.

But if I were talking about my dog for a while, and then said "as for my dog, he can also fly", the fact that we're talking about a flying dog doesn't really change the fact that my dog is already in our realm of conversation, so saying "as for my dog" isn't particularly strange. Likewise, using は in Japanese would be fine, since the dog has already been in people's minds in the conversation.

Also, similarly to "as for" in English, は can sometimes have a contrastive sense in Japanese as well. If, for example, we were talking about your dog, I could then say "as for my dog (as opposed to yours), he can also fly", and using "as for" makes sense even though I'd never mentioned my dog before, because it's in the realm of dogs (which we were already discussing) and I'm contrasting mine with yours.

This actually leads into your question about food. If we're already discussing other types of foods, and you want to talk about a new one, then you can potentially use は, but it will have a bit of a contrastive effect e.g.:

寿司{すし}が好{す}きじゃない -- "I don't like sushi"
寿司{すし}は好{す}きじゃない -- "As for sushi (as opposed to the other stuff we were talking about), I don't like it."

(Edit: I originally had something in here about general vs. specific statements, but as folks pointed out it was a bit misleading and my example was bad for a couple of reasons, so I've removed it. Also adding the following bit:)

It should be noted that one case where this rule of thumb doesn't always work, and Japanese does things differently than English, is when dealing with many negative statements, especially negative states of existence (saying something isn't there). For example, contrast the following statements:

犬{いぬ}がいます -- "There is a dog"
犬{いぬ}はいません -- "There isn't a dog"

When expressing the negative form, the が changes to は, even though according to the "as for" rule of thumb, this seems like it should be odd. That is, what we're essentially saying is:

As for a dog, there isn't one

..even though we may never have made any prior mention of a dog. In English, this is weird, but in Japanese this is perfectly natural (and in fact, using が here would be strange/unnatural in Japanese).

The way I generally think about this is that we tend to use は here because of its contrastive effect. Essentially, if we're saying something isn't there (for example, in a room), the fact that we're stating it is already implying that there probably are some things there, or somebody was expecting there to be something there, it's just that that particular thing isn't one of them, so essentially what we're saying is:

As for a dog (as opposed to the other things around), there isn't one.

This makes some sense in the context of the contrastive は in Japanese, but is really a bit of a stretch in English, so this difference with negatives is really just one of those things you have to keep in mind isn't quite the same when thinking of は in this way.

Answer 2

Ok your question is really quite general about particles, so I'm going to give some general advice.

1: Instead of reducing each individual situation or sentence to a 'do I use wa or ga here?' question, try to think of the overall meaning of the particles instead. If you grasp the deeper meaning of the particles, you will start to understand the answer intuitively. 'wa' marks the topic of a sentence and 'ga' marks the grammatical subject (ie the subject of the verb). That means that sometimes they are interchangeable because sometimes the subject of the verb is also the topic of the sentence. But many times, one or the other is preferred because of the context. A short answer would only leave gaps. My point is that you need to see the grammatical functions of these particles and understand them in the context of the sentences and the meaning within.

2: You don't need to keep repeating a subject. Japanese can be very intuitive, with the listener assuming the subject/topic correctly. You could use the particle も to indicate other things which are included as the subject.

3: As with 1 above, try to see 'wo' as a direct object marker. When a verb has an object, you use 'wo' to mark it (unless replacing it with something like 'mo'). Therefore, there are times when you can use 'wa' instead of 'wo' to contrast something, but in general 'wo' is the default particle to use when marking the object of a verb.

You could write a book on particles and their usage (many people have), so unfortunately you can't get all the answers you need in one reply here. Still, I hope that helped.

Answer 3

I think I know the answers, although I’m a novice.

1. Yes, personal names would practically always take wa when used like shown in your example.

2. No, there are other particles you can use, like mo and ya, etc.

3. Yes, interchangeable.

Answer 4

I am also a beginner, here is what I got.

Let's play a game with English using Japanese grammar.

DogsGA bonesO eatMASU

Compares to

Dogs eat bones.

Now you know ga is essential for a sentence, because it tells you what is a subject from grammar views.

Just imagine if we don't know who is the subject in the following sentence, who beat whom?:

Beats, Bob, John.

ga is so important, you will meet it far more than wa in Japanese.

But what about wa?

There is no such concept in English. wa tells you the topic. In this case, the sentence structure is not

subject verb object

but

Topic wa description

A more accurate translation of wa is: As for

When you introduce yourself, the listeners will know that you are talking about yourself. Can you use ga, If your sentence needs an explicit subject, you can and you have to, since wa does nothing in grammar functions.

What if I provide new information?

wa always switch topics, so if you are talking about something new, you need to use wa.

But the options to this question should be use wa VS omit wa, not wa VS ga

gohan o tabe masu VS gohan wa tabe masu.

I think you have known the answer, gohan o tabe masu means "eat rice", gohan wa tabe masu means "As for rice, eat", you may say it to people that don't know what is rice.