but allow me to ask you a question.....
If you are a native English speaker, then you would have been educated in a native-speaking
school, You would have learned about verbs and adjectives and nouns and pronouns etc etc
etc
But 20 years after leaving school, if you were NOT a teacher, would you remember what an
'adverb' is? What about a 'preposition'?

Twenty years after leaving school I began to study Chinese. As a language student again, of course I had to learn about adverbs and prepositions in the Chinese language. To effectively use them, I certainly needed to know what their function in a sentence is; if the teacher was teaching me fully in Chinese, I would need to recognize the Chinese words for adjective and prepositions. Fortunately, my Chinese language teachers were familiar with English terminology for parts of speech and verb tenses.

Our students are not walking around twenty years after graduation. They are students learning a foreign language.

Too many FTs have never learned a second language. Being a native language speaker, even a well educated one, does not prepare you in TESOL. The experience of learning a second language is invaluable to FTs. Without either training in TESOL or the instructive experience of learning a second language, we often merit the label of dancing monkeys.