The correct passive voice of the sentence `who taught you grammar?` is-
By whom you taught grammar?
By whom grammar was taught you?
By whom was you taught you grammar?
By whom were you taught grammar?
Explanation:
Correct Answer is: By whom were you taught grammar?
Who এর পরিবর্তে By Whom+Tense এবং Person অনুসারে Auxiliary Verb+Object এর Subject+(কোন কোন সময় tense অনুযায়ী Be/being/been ব্যবহ্রত হয়)+verb এর past participle+বাকি অংস?
Who taught you grammar?
-By whom were you taught grammar?