“…During the last decade, many approximate methods have been developed and refined, including the methods of averaging, the boundary layer methods, the methods of matched asymptotic expansion, and the multiple scale methods. Recently, many scholars have done a great deal of work [1][2][3][4][5] . Using the method of differential inequalities and other methods, Mo et al considered a class of nonlinear singularly perturbed boundary value problems for the ordinary differential equations [6] , the reaction diffusion equations [7][8] , a class of activator inhibitor systems [9] , the ecological environment [10] , the shock wave [11] , the soliton [12][13] , the laser pulse [14] , the ocean science [15] , and the problems of atmospheric physics [16] .…”