Grammatical is used to indicate that something relates to grammar.
Should the teacher present grammatical rules to students?
老师应该向学生讲解语法规则吗?
grammatical errors.
语法错误。
If someone's language is grammatical, it is considered correct because it obeys the rules of grammar.
a new test to determine whether students can write grammatical English.
一项考查学生能否用合乎语法的英语进行写作的新型测试。