1、theory英[ˈθɪəri]美[ˈθiːəri]，n.学说; 论; 说; 理论; 原理; 原则; (未证明的)意见; 看法; 推测;

2、[例句]Da Vinci was methodical in his research, carefully recording his observations and theories。达·芬奇搞研究井井有条，会详细记录观察资料和理论学说。