Last learned grammar attrited first compared with those earlier learned items.

后学的语法比先学的先发生耗失。

For Chinese adult learners, their attrition sequence of English grammatical morphemes in Chinese context does follow the "First acquired, last attrited;"

所得研究结果表明：中国成人英语学习者的语法语素磨蚀按照“先习得，后磨蚀；

Seen from a chronological perspective, vocabulary attrition is a process in which unattrited words gradually turn into attrited words under the influences of interfering words.

从历时的角度来看，词汇磨蚀是未蚀词汇在干扰词影响下逐渐变成已蚀词汇的过程。