কোনটি বাক্যটি শুদ্ধ?
Why you have done this?
Why did you have done this?
Why have you done this?
Why you had done this?
Explanation:
Correct Answer is: Why have you done this?
সাধারণ নিয়ম নিম্নরূপ: WH word + have/has + Subject + মূল্য verb এর past participle + extension