Abstract:After Lewis issued his classic essay in 1954,there have been a lot of controversies focusing on some basic and core issues.This paper bases on Lewis's essay and comments on some basic questions and relative disputes,including two sectors,labor surplus and the wage at the subsistence level,classical school foundations and welfare in Lewis's model.Furthermore,the paper also gives some remarks on the development of Lewis's model,especially on the contribution of Fei and Ranis model.The paper make the relations among these models clear and simultaneously correctes some long existing misunderstanding.