Hi all. Seeing as I benefited so much from my previous N2 Grammar question, I thought I'd ask another! I'm now onto test 3 of the Kanzen Green Grammar book (pp.26-28), and had the following questions.

1. In question 1(8), why is the answer 食べまい? Could it not also be 食べない？ I thought まい would be 食べるまい。In any case, surely ない works as effectively here？

2. In question 1(10), この本は図書館から借りたものだから、あなたにあげる＿＿＿＿（しかない、おそれがない、まい、わけにはいかない), why is the answer the last? My understanding of the sentence is that it means "Because this book was borrowed from the library, I ____ give it to you" and the natural answer would be "cannot", not "have to"

3. Question 3(6) strikes me as odd. "理由がないのに、あなたからお金をもらう＿＿＿" answer being わけにはいかない。Surely this means "Though I had no reason to, I had to receive money from you"?

4. Final question - I don't get the difference in use of しかない (no alternative/no option but to) and わけにはいかない (have no other choice but). For example, in question 3(9) (p.28) when you have to choose the most appropriate phrase, why is the answer しかない and not わけにはいかない? (the question is- 終電車が行ってしまったし、お金もないから、歩いて帰る＿＿＿＿)

Thanks for any help possible!

Your issue with 2, 3, and 4, all deal with one simple thing: Your understanding of　わけにはいかない is flipped around.

Look at what they have for the meaning:
A. 理由があって〜できない
動詞、辞書形
"Cannot do ~ because of a reason"
"Cannot do"

B. 〜しなければならない
動詞、ない形
"Cannot (not do) for a reason"
double negative -> must do

If the verb before is positive -> cannot do it. If the verb is negative -> can't NOT do it.

As for #1, I'm not so sure. It looks like they're using the 絶対〜するのをやめよう（否定の意志を表す）meaning, but all their examples do use 辞書形＋まい instead of stem+ない...

Wow, I get it now!! Thanks so much Asriel, I really don't know what I'd do without this forum! Talking things over on here is sooooo useful.

The two meanings for わけにはいかない are completely different then, aren't they - depending on the tense. Haha it seems so obvious now, I just didn't pay enough attention to the explanation.

Cheers for your help dude.

For ~まい, the 2 ways it can be used are "probably won't do" and "will not to."
So, kind of like しないだろう、　and しないぞ！
But you might have knew that already.

In terms of syntax, I can't seem to find any rhyme or reason why sometimes they use stem+まい or verb+まい.
But, in the case of the diet, I think 〜まい would be better than 〜ない because in a manner of thinking it's like a negative version of the volitional 〜よう. You've got the conscious effort of not eating, as opposed to just not eating.

stevesayskanpai Wrote:1. In question 1(8), why is the answer 食べまい? Could it not also be 食べない？

1(8): ダイエット中なので、甘いものは食べ___と思うのですが、なかなか実行できません。

As Asriel says, you need some sort of volitional statement here. This is because of the trailer "なかなか実行できません" ["but I'm finding it hard to keep to it"] -- for this to make sense you need something that says "I'm trying not to [am definitely not going to] eat sweet food" not just "I don't think X eats sweet food". Without that trailing clause, ない would be OK and I think the natural interpretation would be that you're talking about somebody else ("John's on a diet so I don't think he eats sweet foods"). With the trailer you're almost certainly talking about yourself.

Asriel Wrote:I think 〜まい would be better than 〜ない because in a manner of thinking it's like a negative version of the volitional 〜よう.

There are some JLPT1 grammar patterns that contrast まい with よう: 勉強をやろうがやるまいが私の勝手でしょう : whether I study or not is my own decision.

Ok, I see what you mean - a volitional statement would be more appropriate given the context.

Things going well - 1/4 of the way through the book. Hope other people are benefiting from me asking all these questions - more to come I'm sure

Hmm, having studied up to JLPT1 I've never encountered stem-まい once, glad I'm aware of it now.