在這篇論文裡面我們主要是對一些擬線性波方程研究Lipchitz連續解的總體存在性，藉著一次微分的假設當做新的未知數，我們重新把方程式寫成守衡律中的三乘三Hyberlbolic system，這個初始值問題對線性的初始值而言已經被解決了，解的一次微分的整體存在性是藉著Lex method 來建立的。

In this paper we study the global existence of Lipchitz continous solutions to the quasilinear wave equation. By letting the first derivatives as new unknowns, we rewrite the equation into a 3 by 3 hyperbolicsystem of conservation laws. The initial value problem of the ststem is studied for some linear initial data. The global existence of the first derivatives of solutions are established by Lex method.

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