An old dog cannot alter its way of barking. 老狗難改吠聲。

　　An old dog will learn no new tricks. 老家夥學不出新名堂。

　　An old physician, and a young lawyer. 醫生年老的好，律師年輕的俏。

　　An old poacher makes the best keeper. 老偷獵者是最好的看守人。

　　An open door may tempt a saint. 一扇開著的大門可誘惑一個聖徒。

　　An optimist sees an opportunity in every calamity; a pessimist sees a calamity in every opportunity. 樂觀的人在災難中看到希望;悲觀的人在希望中看到災難。

　　An ounce of prevention is worth a pound of cure. 預防勝於治療。

　　An ox is taken by the horns, and the man by the tongue. 牛因有腳而被抓，人因有舌而遭殃。

　　Answer a fool according to his folly. 以其人之道，還治其人之身。

　　An upright judge has more regard to justice than to men. 正直的法官重法勝於重人。

　　A penny saved is a penny earned(or gained). 省錢就是賺錢。

　　A pet lamb makes a cross ram. 寵壞的小羊將成為脾氣壞的大羊。

　　A poor man who takes a rich wife has a ruler, not a wife. 窮漢娶富妻，必受老婆欺。

　　Apothecaries would not sugar their pills unless they were bitter. 好藥不苦不會加糖衣。

　　Apparel makes the man. 馬靠鞍裝，人靠衣裝。

　　Appearances are deceitful. 人不可貌相，海水不可鬥量。

　　Appetite comes with eating. 食欲越吃越旺。

　　A quiet conscience sleeps in thunder. 白日不做虧心事，夜半不怕鬼敲門。

　　A ragged coat may cover an honest man. 不能以衣著取人。

　　Art is long, but lift is short. 人生有涯，而學無涯。

　　A ready way to lose friend is to lend him money. 失友都因借錢起。

　　A road of a thousand miles begins with one step. 千裏之行始於足下。