(1) old用于表示人的年龄。
- How old is he?
他多大了？ - He is seven years old .
他七岁了。
＊上句也可说：He is seven.或者He is seven years of age. 但不说：He is seven years.
(2) 上述表示年龄的说法也可用于物。old还可用于引申意义，常用来表示如：an old story(老一套、老生常谈、常有的事)，an old wives' tale (无聊的话)，an old head on young shoulders (少年老成)，old friend/boy (老同学、老朋友)，old familiar faces (老相识)，old -fashioned (老式的)，to have a good/fine/high/rare old time(过得非常愉快)等。有时，只用来加强语气。
- Any old time will do.
随便什么时候都行。 - Any old thing will do.
随便什么东西都行。
(3) 其他短语还有：an old hand at sth. (老手)，the old man (是美式俚语，用作对丈夫、父亲、船长、主管人、校长、军队长官等的亲切称呼，当面称呼时去掉the)，old folks (老人们、老夫妇)，在美式口语中特指家里人。
(4) old还可表示旧的、以前的、旧式的。如：old dresses, old job, old customs, the old world。
(5) of old意为“古时候(的)，过去(的)”，如：in days of old。
- Knights of old had to wear armor in battle.
古时候骑士在战斗中必须穿盔甲。 - The ladybug took wing(s) and went off to see about it — which did not surprise the boy, for he knew of old that this insect was credulous about conflagration.
瓢虫展翅飞去了，它要去看个究竟——这并不使那个男孩感到惊奇，因为他过去就知道，一讲到大火，这种昆虫就容易受骗上当。
(6) olden意为“过去的，从前的”，多用于书面语或诗歌中。
- The talking was about the olden times.
这故事是关于旧时光的。
(7) “自古以来”常用的说法：from ancient times, from days of old, from of old, from time immemorial等。from olden times, since time immemorial, from days of yore等，常用于文学作品中。
