在听说教学法中，教师不必解释文法。

In audio-lingualism, there is no explicit grammar instruction.

youdao

如果在同一个文件里混用多种语言，必须保证文法不会出现二义性，也就是说所有的输入都只能存在一种解释。

If you want to combine languages inside of a file, you have to be sure that the resulting grammar isn't ambiguous, i.e. that for each input there is only one way to interpret it.

youdao

两名英语老师在解释文法规则和词汇方面花费了大量的努力和多数时间。

The two English teachers in the study spent great efforts and most of the time explaining the grammar rules and vocabularies.

youdao