That song has stuck in my head for years.那首歌多年来一直铭记在我心中。We decided to uproot and head for Scotland.我们决定迁往苏格兰。The film's haunting musical theme stayed in my head for days.那部电影挥之不去的主题旋律多日来萦绕于我的脑际....
绝大多数非线性微分方程是不能用解析方法求解的.The overwhelming majority of nonlinear differential equations are not soluble analytically.与微分相反的运算叫做积分.The operation that is the inverse of differentiation is called integration.这称为正规微分方程组.This is...