JLPT N2 › Conjugation 口が重い · i-adjective
Form Positive Negative Dictionary 口くち が 重おも い 口くち が 重おも くない Polite 口くち が 重おも いです 口くち が 重おも くないです also 口くち が 重おも くありません Past polite 口くち が 重おも かったです 口くち が 重おも くなかったです also 口くち が 重おも くありませんでした Past 口くち が 重おも かった 口くち が 重おも くなかった Te-form 口くち が 重おも くて 口くち が 重おも くなくて Adverbial 口くち が 重おも く Conditional 口くち が 重おも ければ 口くち が 重おも くなければ Tara conditional 口くち が 重おも かったら 口くち が 重おも くなかったら
Kanji 重 heavy, important, esteem Related words 無口 describes someone's general personality as quiet or taciturn, while 口が重い often points to a specific reluctance or heaviness in speaking, sometimes just in the moment.
寡黙 is a more literary, formal word for being habitually quiet, whereas 口が重い is an everyday idiom that can describe either a personality trait or a temporary state.
Don't confuse with 口が堅い means someone is discreet and keeps secrets well, which learners often confuse with 口が重い since both use 口が + adjective, but 口が重い is about reluctance to speak, not trustworthiness.
口が悪い describes someone who speaks harshly or has a foul mouth, a very different meaning from 口が重い , which describes someone who barely speaks at all.
Etymology The expression literally means 'the mouth is heavy', metaphorically likening reluctance to speak to a heavy object that is hard to move.
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