-kucha & -n

i hope anybody can help me with tis thing.

1. i often find a verb combining with "-kucha" in the end of the word. such as 'ikanakucha' ect.

2. and i find this more, an '-n' in the end of verb. like, iku-n darou, ect.

so what's "-kucha" and "-n" mean and in what condition usually used?
thanks before.

They are simply grammar structures:

negative stem + kucha (+ ikenai) is an abbreviated form of the [verb]～なくてはいけません, meaning "must do [verb]" (literally, "it is not alright to not do [verb]")

the ん following a plain form verb serves to emphasize the verb as a part of an explanation of sorts (or a question asking for more information regarding the verb). It can be a fairly subtle nuance, but very useful in a number of situations. I commonly use it when I'm asking for directions: "すみません、東京駅まで行きたいんですけど。。。" and "how do I get there" is implied. Even without the ん it's still perfectly understandable, but I suppose it's a more subtle way of implying that there is more to be said.

There is more written on this grammar point elsewhere in the learning Japanese forum. Please poke around for more info, or continue to ask questions here if you are still unsure on the subject.

(thank you for the info. i'll explore the forum next)

so if i wanna say "must go to school", it goes "gakko ni ikanakucha", like that?
and
"dou shite tabenai-n desu ka" simply mean "why you don't eat", right?

actually i still dont understand in what situation i can use the ん
guess i should analyzing many many similar sentences.

Oh, sorry i forgot to ask tis one:
otonabichatte, yowatchau, kotchatta,...
why the "-ru" changed to be "-chau/-tcau"??

mico said:

so if i wanna say "must go to school", it goes "gakkou ni ikanakucha", like that?
and
"dou shite tabenai-n desu ka" simply mean "why you don't eat", right?

Click to expand...

These are fine sample sentences, and appropriate uses for the grammar points you asked about. One thing I must point out is that the "～なくちゃ" abbreviation is a less polite form of "～なくてはいけません," so you shouldn't use it when talking to someone that is 目上 (older or in a higher position than you on the social ladder, so to speak).

Oh, sorry i forgot to ask tis one:
otonabichatte, yowatchau, kotchatta,...
why the "-ru" changed to be "-chau/-tcau"??

Click to expand...

This is another example of the abbreviation of a grammar form. In this case, ～てしまう (to do something completely, or to do something that might have negative consequences). If you look up ～てしまう, you'll probably find an entry that covers this abbreviation as well.

Just curious, are you teaching yourself, or do you have some kind of formal instruction in Japanese?

i don't have time to take a japanese course. so i learn japanese by doing simple analyze to sentences and grammar from L'Arc~en~Ciel's song . tis way is more helpful to me than learning from any Nihon go no bumpo books (coz they're not complete, alias just for basic learning, rite?)
are you asking this bcoz i ask for impolite forms?? oh, my....then i better avoiding using those form

......do you think i will get any trouble like, misunderstanding/mislearning of japanese if i learn that way?

people tend to misunderstand or mislearn (if that's a word) no matter what their methods are, but I can't say I condone learning from songs. One reason being that they tend to bend the rules of the language in order to fit with the melody or rhythm of the music.

If you really want to study on your own and just analyze grammar structures, I recommend the Japan Times Dictionary of Basic Japanese Grammar. There is also an Intermediate version published, and an Advanced one is on the way.

is that so?

i never found the book in stores i always visit to. but thank you for the recomendation. i'll search it harder in every book stores here.

The thing about the dictionary of grammar is that it doesn't have any lesson plan. It's a dictionary, so all of the structures are simply listed according to the sound they start with.

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