てやまない

てやまない says a feeling never lets up: you wish, hope, love or respect from the bottom of your heart. It goes on the て-form of a verb of feeling. やむ means "to stop", so the literal sense is "does not stop".

Which verbs

Only a handful of verbs take it: ねがう願う, いのる祈る, のぞむ望む, あいする愛する, そんけい尊敬する, きたい期待する. An action does not work, however often you do it.

• × 毎日走ってやまない → 毎日走り続けている

Register

てやまない is written and ceremonial: speeches, formal letters, the closing line of a greeting. Its polite form やみません ends many such texts. In conversation you would say こころ心からねがっています願っています or ほんとうに本当にそんけい尊敬しています.

てやまない or てたまらない

Both describe a strong feeling. てたまらない is a sensation you can hardly bear right now – hunger, heat, wanting something – and is everyday speech. てやまない is a lasting sentiment, usually a wish for someone else, said formally.