fall down
be shown to be false or inadequate; collapse 顯示不實或不足; 崩潰; 失敗
The plan fell down because it proved to be too expensive. 這項計劃因費用過高而告吹. fall down on sth (infml 口) fail to do sth properly or successfully 沒有把某事做好
fall down on one's promises 未履行自己的諾言
He fell down on the job. 他未能把這件工作做好.