has to be done
Structure
- Casual Suffix
- Verb[な
い]・くちゃ・いけない- Verb[な
い]・きゃ・いけない
[short form・casual・colloquial]
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Can you tell me the rule here? When is the answer くちゃ・いけない, and when is it きゃ・いけない? I can’t seem to figure it out at all. Thank you!
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I think it’s either/or, isn’t it? At least, that’s the assumption I’ve been operating under.
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@Marcus, @eefara is right.
There is virtually no difference in meaning.
The etymology is different though.
なきゃ comes from なければ (another contraction is なけりゃ)
なくちゃ comes from なくては (there are some variations, like なくっちゃ).
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Thank you!
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If these are equivalent then what am I missing regarding the difference…
Why is なきゃ the only acceptable answer for this particular question? I must be missing some key aspect of this lesson???
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Both answers are proper and acceptable 
Your understanding is correct!
Then is it a bug that it doesn’t accept the other answer? When you click “a” it only shows the one options as correct?
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It seems so,
かいにいかなくちゃ
かいにいかなくちゃいけない
かいにいかなきゃ
かいにいかなきゃいけない
かいにいかなくちゃだめ
are all accepted answers (among others). 
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hence my confusion/frustration 
if it’s a bug that’s great…means I’m only a little less dumb than I thought I was 
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With this grammar point what’s confusing to me is the readings indicate you can just use なくちゃ or なきゃ without adding いけない but all of the examples include いけない. why is that if the point of these two suffixes are meant for shorter, more casual sentences?
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Hey 
Sorry for the late answer
So basically, we weren’t using なくちゃ and なきゃ by itself in sentences, since the grammar point aims to train the whole phrase.
Though they are accepted as alternative answers while reviewing.
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So, I got to this example which tripped me up a bit:
暑いので水をのまなきゃいけない
As I find myself questioning if のま or のみ should be used for this and some other grammar points as I don’t recall being taught any rule for it. I had to look it up and learned that it’s the “causative form”, but I don’t believe there was a lesson on causative forms before this?
Is there some sort of hard and fast rule? My guess here would be that because it’s a result of something else (it being hot out) that there is a “cause” for it and thus it uses this form, correct?
(though that then brings up the question of why the negative of a verb uses the causative form as well, being one of the earliest lessons making us use this form)
Thanks.
@Invertex Hey! 飲まない is the casual negative conjugation of 飲む. Since grammar constructions like なくちゃ and なきゃ require that the verb first be conjugated to the negative form (飲む → 飲まない → 飲まなくちゃ/飲まなきゃ) verbs that end in む will conjugate to ま (飲む, 込む, 読む, etc.). Hope this helps! Cheers.
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Ah okay, that makes sense. So for most expressions/terms that start with な, the verb before them should be in the negative form? Or are there exceptions to this?
Not sure I get what you’re trying to generalize here. This specific grammar point (as well as the non-shortened versions) require the preceding verb to be conjugated into the negative form first. Other expressions don’t really come into play.
I’d assumed since it was listed as なくちゃ that the な was part of the phrase itself, but I guess the phrase is just くちゃ/きゃ like it shows split up in the structure section. So in my mind when I wrote that I was imagining similar things that “start” with な without first knowing if it required the negative form before it. It’s all good though.
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