waste away
phrasal verb with waste verb [ T ] uk/weɪst/ us/weɪst/
逐渐消瘦；渐渐瘦弱
to gradually get thinner and weaker, in a way that is unhealthy
You get thinner every time I see you, Sara - you're wasting away! 我每次见你你都比以前瘦了，萨拉——你真是越来越瘦弱了！