Explanations of the Grammar from Betty Azar's Understanding and Using English Grammar
"I think it's important to recognize that grammar terminology and grammatical analysis are only a means to an end, never ends in themselves in the ESL classroom. Often the teacher finds it useful to have temporary labels (simplified grammar terminology) in order to answer students' many questions and show students how English works.
Terminology (e.g., "present perfect" or "noun clause") can be forgotten as soon as students leave the English class with no ill effects. These terms are just temporary teaching tools. Once students leave a program of language instruction, it seems to me they need only enough terminology to help them use a dictionary or reference book effectively (should they have the need), roughly the same grammar terminology a typical educated native-speaker of English benefits from knowing: noun, verb, adjective, sentence, comma, etc. The deeper understandings of structural patterns that help with reading comprehension and the expression of complex ideas will remain without or without students being able to recall grammar terminology. The terminology is not what's important: it's the understanding of the structures and how form conveys meaning.
The use of simplified grammar terminology in the ESL classroom is just a tool, a way of helping students understand patterns in the language. In my experience, adult students "get" patterns of form and meaning from understanding examples -- how they work, what's happening, how ideas are put together and interrelated. Explanations, which can come in many forms, are used only "as needed." What we're after is for the students to understand -- deductively, inductively, or any mixture of the two -- examples of usage, to "see" how they work structurally. Leveraging our adult students' cognitive skills can be beneficial as they develop their interlanguage, but it's just one part of a well-balanced classroom. At any rate, mastery of terminology or skill at parsing is never what we're after."
Betty S. Azar