Complex sentence: After Taishi Ci returned from Liaodong, his mother told him, You may not have met Kong Rong, but he has been treating me very generously--almost like an old friend--while you were away.
Split into simpler sentences: After Taishi Ci returned from Liaodong, his mother told him, You haven't met Kong Rong. He has been treating me very generously--almost like an old friend--while you were away.