JLPT N3 Partial and strong negation
わけではない and とは限らない soften a claim into "not necessarily", while わけがない and 決して～ない deny it outright. めったに～ない means "rarely", 別に～ない "not particularly", and ないことはない is a hedged "it's not impossible". The double negative in ないことはない is often misread as a plain negative.
9 N3 grammar points in this group
別に～ない (betsu ni nai): not really; not particularly
Use 別に～ない（べつに～ない） when you want to downplay a feeling, preference, or state; answer casually to questions about likes or opinions.
別に用がないんですが。 — I don't really have any particular business.
めったに～ない (metta ni nai): rarely; hardly ever
Use めったに～ない when you want to say something almost never happens.
彼はめったに怒らない。 — He rarely gets angry.
決して～ない (kesshite nai): never; by no means
Use 決して～ない（けっして～ない） when you want to strongly deny or emphasize that something is not true.
この秘密は決して誰にも言いません。 — I will never tell this secret to anyone.
とても～ない (totemo nai): cannot possibly; not at all able to
Use とても～ない when you want to strongly say that something is impossible or beyond ability.
この量は一人ではとても食べられない。 — I cannot possibly eat this amount alone.
わけではない (wake dewa nai): it does not mean that
Use わけではない when you want to deny a conclusion while leaving part of the situation true.
日本語が嫌いなわけではない。 — It is not that I dislike Japanese.
とは限らない (towa kagiranai): not necessarily; not always
Use とは限らない（とはかぎらない） when you want to deny that a general statement is always true.
高い物が必ずいいとは限らない。 — Expensive things are not necessarily good.
わけがない (wake ga nai): there is no way
Use わけがない when you want to strongly say that something is impossible or cannot be true.
彼がそんなことを言うわけがない。 — There is no way he would say something like that.
ないことはない (nai koto wa nai): not impossible; can do somewhat
Use ないことはない when you want to give a double-negative, reluctant possibility.
行けないことはないが、少し遠い。 — It is not impossible to go, but it is a bit far.
ずに (zuni): without doing
Use ずに when you want to say one action happens without doing another expected action.
朝ご飯を食べずに学校へ行った。 — I went to school without eating breakfast.
Often confused in this group
- わけだ vs わけではない vs わけがない vs わけにはいかない — わけだ draws a conclusion, わけではない softens a denial, わけがない rules something out, わけにはいかない means you can't for social reasons.
More JLPT N3 grammar groups
- Conditionals, wishes, and regrets (10)
- Contrast and concession: even if, although (13)
- Cause, reason, and result (9)
- Purpose, intention, and effort (14)
- Obligation, advice, and no choice (15)
- Hearsay, conjecture, and appearance (15)
- Time, timing, and gradual change (20)
- Relational phrases: about, for, through (19)
- Compound verbs and suffixes (20)
- Degree, comparison, and emphasis (20)
- Adding, listing, and connecting ideas (18)