He did not mean by this word that you were a liar. (Interrogative)

Assertive Sentence কে Interrogative করতে হলে Affirmative- Negative হয়, আর Negative হলে Affirmative হয়।
Interrogative শুধু Principal Clause কে করতে হয়। (He did not mean by this word)
Sub-ordinate Clause সর্বদা Assertive Sentence হয়। (that you were a liar.)