1. 与具体数字连用时，不加复数词尾 –s；若后接名词，通常也无需用介词of。如：
I’d like three dozen altogether. 我想一共要3打。
There was only space for a half-dozen tables.
只有摆六张桌子的地方。
He sat behind a table on which were half a dozen files.
他坐在一张放有6个文件夹的桌子后面。
A group of half a dozen men entered the pub and bore down on the bar
一伙六个人走进酒吧，冲向吧台。
He had come half a dozen times to call upon his sister.
他曾来过五六次看他的姐姐。
In half a dozen words, he had explained the bond that linked them
他用了六七个字就解释清楚了他们之间的关系。
Only about half a dozen people turned up.
只有六七个人到场。《牛津高阶英汉双解词典》
He had two dozen oysters and enjoyed every one of them.
他吃了两打牡蛎，每一只都吃得津津有味。
Garbo made two dozen films, first silent pictures then talkies.
嘉宝拍过24部电影，先是无声的，后是有声的。
The Bible states that the life of man is three score and ten.
《圣经》中说人的寿命是70年。
The company already has around four score titles commissioned and planned for publication
那家公司已有约80本书委托好了作者并计划出版。
He has lived here for two score years. 他已在这儿住了40年。
偶尔也可见到受具体数字修饰的dozen, score后接 of，但惯用法认为省略 of则常见。
2. 若不与具体数字连用，而是表示不确定的泛指数时，则不仅要加复数词尾 -s, 而且要后接介词of，然后才能接名词。如：
I've been there dozens of times.
我到那里去过很多次。
Dozens of reporters camped out on her doorstep.
许多记者在她家门口露宿。
There were dozens of people there. 那里有许多人。
There were scores of boxes and crates, all waiting to be checked and loaded.
大批的箱子和板条箱等着检验后装运。
Lightning strikes caused scores of fires across the state.
雷击给整个州造成了数十起火灾。
I have heard of that scores of times. 那件事我已听过很多遍了。
3. 当与a few, several, many等数目不很具体的词连用时，带不带复数词尾 -s均可，但是注意：若不带复数词-s，其后的介词of可以省略；若带复数词尾-s，则其后介词of不能省略。如：
The company employs no more than a couple of dozen people.
这个公司顶多雇用了几十个人。
several dozen(s) of eggs=several dozen eggs 几打鸡蛋
several dozen (of) pencils= several dozens of pencils 几打铅笔
4. 若其后的名词受the, these, those等特指限定词的修饰，或其后接的是us, them 这样的人称代词时，则此时必须用介词of。如：
He ordered a dozen of their best red roses.
他订购了12朵他们那儿最好的红玫瑰。
a dozen of his friends 他的一打朋友
two dozen of them 它们中的两打
three score of these eggs 这些鸡蛋中的60只
注意：a dozen也表示不确定的十几个：
The soup was concocted from up to a dozen different kinds of fish.
这种汤是用多达十几种不同的鱼熬制而成的。
I was sitting only a dozen feet away.
我正坐在只有十几英尺远的地方。
He has reversed himself on a dozen issues.
他已经不再坚持自己在一系列问题上的立场。
There was a big group of a dozen people at the table next to theirs
他们旁边的桌上坐了一大群人，有十几个。
Two people were killed and scores were injured.
两人死亡，多人受伤。
A score of countries may be producing or planning to obtain chemical weapons...
大概有20个国家可能正在制造或计划获取化学武器。
Several cabs and a score of cars were parked outside.
外边停着二十几辆汽车和几辆出租车。
He gave me a baker's dozen of doughnuts.
他给了我十三个甜甜圈。
He bought a baker's dozen of biscuits.
他买了十三块饼干。