洞口大半都淹没在湖里。Most of the mouth of the cave was submerged in the lake.湍急的水流奔涌过洞口。The water rushed through the holes with great rapidity.两艘船隆隆地从洞口开出，进入了开阔的水域。Both boats purred out of the cave mouth and into open water....
位势方程在十八世纪关于引力的研究中已显露头角.The potential equation had figured in the eighteenth - century work on gravitation.引入随机正则函数和随机位势函数的概念.The concepts of random regular function and random potential function are introduced.三维薛丁格方程式: ...