N2 — outside your level filter
Is said whole, with nothing composed onto it and takes no だ／です, so there are no forms to conjugate.
口が重い
kuchigaomoibe slow to speak, taciturnN2expression
Example sentences2
彼は口が重いので、何を考えているか分かりにくい。
kare wa kuchi ga omoi node, nani o kangaete iru ka wakarinikui.
He's slow to speak, so it's hard to tell what he's thinking. neutral
うちの父は口が重いから、あまり話さない。
uchi no chichi wa kuchi ga omoi kara, amari hanasanai.
My dad is a man of few words, so he doesn't talk much. casual