regular: stresses conformity to a rule, standard, or pattern: the ~ monthly meeting of the organization.


normal: implies lack of deviation from what has been discovered or established as the most usual or expected: ~ behavior for a two-year-old boy.


typical: implies showing all important traits of a type, class, or group and may suggest lack of marked individuality: a ~ small town in American.    (trait属性基础词，因此不需解释，例如瞳孔颜色)    group组织


natural: applies to what conforms to a thing's essential nature, function, or mode of being: the ~ love of a mother for her child. (essential本质是指最重要，如果改变会导致整个事物改变的东西，如conflict is an essential element in drama冲突是戏剧的本质要素，但这里nature天性是主要意思，所以没有标红essential)


regular常规例行: 表示符合规则标准模式，normal通常正常: 表示不偏离通常预期，typical典型: 表示具备某类型群组的所有属性，也表示缺乏个性，natural自然天性: 符合本质天性模式功能


记忆方法: 1）首字母RNTN想成如你同你<==做事符合常规

         2）常规的意思是符合通常预期mean being of thesort or kind that is expected as usual, ordinary, or average.  （expect预期预计: 认为有较大可能发生, I expect to finish the work by 11 o'clock我预计11点能完成） usual通常，强调不奇怪，和normal同义，较随意，my usual order for lunch我通常点的午饭。