Who called you a liar? বাক্যের passive voice হচ্ছে-
Who called you a liar? বাক্যের passive voice হচ্ছে- Correct Answer By whom were you called a liar?
Who called you a liar? বাক্যের passive voice হচ্ছে - By whom were you called a liar? মূল sentence 'past indefinite' হাওয়ায় you এর auxiliary verb হিসেবে were বসবে।