The present disclosure provides a method for processing sentence, including: determining a vector representation of a sentence to be processed; inputting the vector representation of the sentence to be processed to a first recurrent neural network, and updating a state of a hidden layer of the first recurrent neural network as a vector representation of a historical dialogue, wherein, if a processed sentence exists, the state of the hidden layer of the first recurrent neural network is related to the processed sentence; determining a knowledge vector related to the sentence to be processed; and generating a reply sentence based on the vector representation of the historical dialogue and the knowledge vector. The present disclosure further provides a system for processing sentence, an electronic device, and a computer-readable medium.