[masaegu]

Originally Posted by murasaki11

When my Japanese friend hear me say カレシがいない he said it sounds like "my boyfriend has dissapeared". I got very confused about this whole thing because none of my books and learning tools for japanese go deep into the situation, so its VERY hard to get a grasp on what to use in these situations.

Right. Please know that you asked a very good question yeterday. I am sure many others will thank you for it. I have said this here multiple times without receiving any reactions but will say it again. Studying Japanese means studying its particles. Just like 「は」 and 「が」, the simplest-looking single-syllable words are the most difficult to use. There are even books on just these two particles.

I, as a Japanese-speaker, have naturally never learned Japanese outside of Japan. From helping people learn it for 30 years, however, I have a pretty good idea of how it is taught. I can clearly "see" that they are not very strict on the use of 「は」 and 「が」 but I can kind of understand why, too. Be strict with beginners and you will lose students.

If
「カレシがいない。」 means "My BF is missing!", "My BF has disappeared!", etc. and
「カレシはいない。」 means "I have no BF.",
anyone should be able to tell instictively that 「は」 and 「が」 are not interchangeable and they are monsters of words. The first sentence says that you have a BF and the second, that you do not. Isn't that a huge difference?

Use 「が」 when describing an unusual situation, accident, extraodinary event, etc.

"The sky is blue."
"OMG, the sky is dark grey!"
Now you know which one requires which particle if said in Japanese, dontcha?

Anyone willing to tell me which one is a construction worker? The other guy is probably a baseball player.
Guy A: "I broke the window." said with 「ボクが」
Guy B: "I broke the window," said with 「ボクは」

As for what I think the translations are, this is what I was taught.

I was taught that ある and いる 's translation depends on the situation. I was taught they mean "existance" and wether something is here being situated in an area, or someone "has" something, to possess something.

But what I've always been taught, is not matter what, you always use が regardless on what you what to empasize.

Wow, no wonder why you are confused. The "normal" subject marker is 「は」. You need a reason to use 「が」. This may sound simplistic but it should capture the essence of the matter.

My books and information sourses never took into concideration wether you are talking about "a thing" or "the thing". Or something you already know about, or something you are just asking if someone has. It always implied that it doesn't matter in Japanese, that you just state the object and that there is no "the, a", specifying more information about a object.

I almost want to hug you for the misfortune you have gone through. You deserve better "sources". The beginning stage is so critical in foreign language acquisition.

What i've been taught that these translations all mean,

かぎがある。 (I) have key Particular keys.
かぎがある？Do (you) have key? Sounds strange. Use 「は」 though it still wil sound strange. I do not know what 「かぎがある？」 even means.
(regardless if your talking about a specific key, or a key in general).

かぎがありますか (same thing but polite) For questions and negative statements, use 「は」.
かぎがない。 (I) don't have key. Particular key(s) and you are being unable to find it/them. Remember "My BF is missing!"?

犬がいる。 (I) have dog. Means both "I have a pet dog." and "There is a dog (here/there)."
犬がいる？ Do (you) have dog. We do not really say this to mean anything.
犬がいますか Same but polite Use 「は」.
犬がいない。 (I) Don't have dog　　Does not mean that. Means "My dog is missing!"[quote]

I though that these sentences could be used in all different situations, from wether your asking someone if they have these things in general, or if your asking if they had these things with them, something they already knew existed.

Again, it is never that simple but please give yourself lots of time to become able to feel comfortable with the particles. Developing these "feelings" is not easy. Keep writing/speaking and keep getting corrected by someone you trust.