口を付ける
くちをつける to taste to try (food or drink)

口を入れる
くちをいれる to throw in a suggestion

口を出す
くちをだす to interrupt a conversation

口を割る
くちをわる to confess to speak out

口を慎む
くちをつつしむ to be careful in speech

口を拭う
くちをぬぐう to wipe one's mouth to feign innocence to feign ignorance

口を挟む
くちをはさむ to cut into (a conversation) to interject

口を掛ける
くちをかける to apply for (a job) to call for (a doctor)

口を揃えて
くちをそろえて (to complain) unanimously in chorus

口を極めて誉める
くちをきわめてほめる to be lavish in another's praise

口を窮めて誉める
くちをきわめてほめる to be lavish in another's praise