Connects two clauses to mean 'even though / despite', but unlike simple ~のに it carries a strong tone of blame, criticism, contempt, or complaint aimed at the subject. Use it when you find someone's behavior inconsistent or unfair — 'even though he knows, he pretends not to'. It should not be used about oneself in a neutral way.
[Verb/い-adj plain] / [な-adj + な] / [Noun + の] + くせに
知っているくせに、教えてくれない。
Shitte iru kuse ni, oshiete kurenai.
Even though he knows, he won't tell me.
知っている (plain) + くせに adds a reproachful 'and yet'
子供のくせに生意気だ。
Kodomo no kuse ni namaiki da.
He's cheeky for a mere kid.
子供 (noun) + の + くせに = 'despite being only a child'
下手なくせに、いつも自慢する。
Heta na kuse ni, itsumo jiman suru.
He's bad at it, and yet he always brags.
下手 (な-adj) + な + くせに carries a scornful nuance
• Always emotional/critical — never neutral. Avoid in polite or formal contexts. • The subject of both clauses must be the same person. • Can be left dangling as ~くせに。 to imply blame without finishing the thought.
The JLPT rarely asks whether you recognise a pattern — it asks which of several similar patterns fits. These are the ones ~くせに is tested against.
のに is a neutral 'even though' expressing surprise or regret; くせに always adds personal blame, contempt or complaint toward the subject.
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