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intolerable; unbearable; unendurable
irresistible; tremendous; out of this world
cannot help (doing); cannot but do; anxious to do; cannot get enough of
今日の暑さは本当にたまらない。
Today's heat is really unbearable.
夏の暑さがたまらないので海に行きたい。
The summer heat is unbearable, so I want to go to the beach.
優勝が決まって嬉しくてたまらなかった。
I was so happy I couldn't contain myself.