なるのではないか/なるのではないだろう meaning


もっと人間関係を大切にすれば、100年前と同じような心豊か生活が送れるように _______ と思う。

  1. なるのではないか
  2. なるのではないかな
  3. なるのではないだろう
  4. なるのでないでしょう

1 is the correct anwser but I can't figure out why. I guess 4 is incorrect
because it uses the です form. Is なるのではないか just a set phrase? Does なるのではないだろう
need か to be grammatically correct? Could someone please break down these
phrases?




> Does なるのではないだろう need か to be grammatically correct?

No. All are grammatically fine. They can be used in appropriate sentences.

> Is なるのではないか just a set phrase?

Practically I think it's better for learners to treat (の)ではないか as a pattern,
as many Web resources seem to do. _Sentence + のではないか_ means _isn't it the case
that Sentence?_

The importance of か here is to add doubt. Without it, it is a simple negative
sentence. It would mean _(I think) it isn't the case that we will live
better_. By adding か, doubt+ではない works like a double negative=positive,
meaning _I think it **is** the case that we live better_. Or, as mentioned
above, it makes a (rhetoric) question: _isn't it the case_ (I wonder, isn't it
the case that ...?, yes it is).

* * *

I think 2 fits ok, too. 1 is correct probably because it is about のではないか as a
pattern.

Also, なるのではないだろう **か** can work (3+か).

