We Know Already That The Simple Past Of The Verb To Be Is Was/were.in A Sentences I Write: I Was Studying......., But Why In The Conditionals I Write: If I Were.......? As A Future English Teacher. How Can I Explain This To My Students The Use Of Was/were In The First Person Singular?
1. If I were you, I'd buy a new baseball cap.
The "were" in #1 is an example of the past subjunctive, which uses "were" in all persons, singular and plural.
The past subjunctive in an if-clause expresses a "contrary to fact" situation ("I" am not "you"). It doesn't have temporal significance.
You could explain it as a past tense form, rather than a past tense; just as the past tense form in #2 suggests speculation, rather than real past-ness:
2. If you bought a new baseball cap, women would find you irresistible.
Does that help at all?