Grammar is the ways that words can be put together in order to make sentences.
He doesn't have mastery of the basic rules of grammar.
他没有掌握语法的基本规则。
the difference between Sanskrit and English grammar.
梵语和英语语法之间的区别。
Someone's grammar is the way in which they obey or do not obey the rules of grammar when they write or speak.
His vocabulary was sound and his grammar excellent.
他的词汇量丰富,语法也很棒。