[没齿难忘 / 沒齒難忘, mò chǐ nán wàng, ㄇㄛˋ ㄔˇ ㄋㄢˊ ㄨㄤˋ]hard to forget even after one's teeth fall out (成语 saw); to remember a benefactor as long as one lives; undying gratitude#103893[Add to Longdo]
[没齿不忘 / 沒齒不忘, mò chǐ bù wàng, ㄇㄛˋ ㄔˇ ㄅㄨˋ ㄨㄤˋ]hard to forget even after one's teeth fall out (成语 saw); to remember a benefactor as long as one lives; undying gratitude#180616[Add to Longdo]