knight of the grammar

例句：

1. 1. He is a renowned grammarian who has written many books on the subject.
   他是一位著名的语法学家，已经写了许多关于这个主题的书。
2. 2. The grammarian was invited to give a lecture at the university.
   这位语法学家被邀请在大学发表演讲。
3. 3. Grammar is an essential part of learning a language.
   语法是学习一门语言的必不可少的部分。