てもいい (te-mo-ii) vs なくてもいい (nakute-mo-ii)
What's the Difference?
Quick Answer
Use てもいい to express permission, and なくてもいい to express the absence of obligation. The key difference lies in their implications: てもいい implies it's okay to do something, while なくてもいい implies it's okay not to do something.
Side-by-Side Comparison
| Aspect | てもいい (te-mo-ii) | なくてもいい (nakute-mo-ii) |
|---|---|---|
| JLPT | N4 | N4 |
| Formality | neutral | neutral |
| Permission vs Obligation | Expresses permission to do something | Expresses the absence of obligation to do something |
| Implication | Implies it's okay to do something | Implies it's okay not to do something |
| Context | Often used in situations where someone is seeking permission | Often used in situations where someone wants to reassure or inform about the lack of necessity |
| Tone | Can be used in both positive and negative contexts | Generally used in a neutral or positive context to relieve obligation |
てもいい (te-mo-ii)
JLPT: N4 | Formality: neutral
- Permission vs Obligation: Expresses permission to do something
- Implication: Implies it's okay to do something
- Context: Often used in situations where someone is seeking permission
- Tone: Can be used in both positive and negative contexts
なくてもいい (nakute-mo-ii)
JLPT: N4 | Formality: neutral
- Permission vs Obligation: Expresses the absence of obligation to do something
- Implication: Implies it's okay not to do something
- Context: Often used in situations where someone wants to reassure or inform about the lack of necessity
- Tone: Generally used in a neutral or positive context to relieve obligation
Example Sentences
てもいい (te-mo-ii)
今日は休んでもいい
kyō wa yasun de mo ii
It's okay to take the day off today
このドレスを着てもいい
kono doresu o kite mo ii
You may wear this dress
友達と遊んでもいい
tomodachi to ason de mo ii
You may play with your friends
なくてもいい (nakute-mo-ii)
今日は来なくてもいい
kyō wa konakute mo ii
You don't have to come today
この問題を解くなくてもいい
kono mondai o toku nakute mo ii
You don't have to solve this problem
お金を払わなくてもいい
ōkan o harawanakute mo ii
You don't have to pay
Common Mistakes
- ⚠ Using てもいい when trying to express the absence of obligation, which can lead to confusion about what is being permitted.
- ⚠ Using なくてもいい in situations where permission is being sought, which can lead to misunderstandings about what is allowed.
- ⚠ Not considering the context and tone when choosing between てもいい and なくてもいい, leading to inappropriate expressions.
Memory Tip
💡 Remember that てもいい has 'te' which sounds like 'take' or 'do', implying you can do something, whereas なくてもいい has 'naku' which implies not doing something, making it about not having to do it.
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