Identify the correct passive form of the sentence.
"Who guided you through the intricacies of mathematics?"

Active Voice: Who guided you through the intricacies of mathematics?
Passive Voice: By whom were you guided through the intricacies of mathematics?

→ Active Voice-টি Past Indefinite Tense- এ আছে এবং এটি Interrogative Sentence.

Who-যুক্ত Sentence-কে Interrogative করার নিয়ম:
→ Who-এর পরিবর্তে প্রথমে By whom বসে +
→ Tense ও Person অনুযায়ী Auxiliary Verb বসে +
→ Objectটি Subject হয় +
→ অনেক সময় Tense অনুযায়ী, কর্তার পরে be/being/been বসাতে হয় +
→ মূল Verb-এর Past Participle হয় +
→ প্রশ্নবোধক চিহ্ন বসে।

More Examples:
Active Voice: Who inspired you to pursue a photography career?
Passive Voice: By whom were you inspired to pursue a photography career?

Active Voice: Who introduced you to classical music?
Passive Voice: By whom were you introduced to classical music?

Source: Advanced Learner’s Communicative English by Chowdhury and Hossain.