表达所属时，可以用“’s”。撇号是个很有用的符号。例如，当你想表达“我们邻居家的狗”时，不必用
the dogs owned by our neighbor
而可以用
our neighbor's dogs
来表示。
以“S”结尾的名词加上‘s 时，读起来很拗口，有人在这些名词之后只加撇号。例如：
James' friends
在审读你的作文时，要注意是否在该加撇号的地方加上了撇号。
应该怎么修改下面这个句子呢？
A persons instincts are sometimes correct.
有时候作者把撇号放错了地方。例如，在下面这句话里，撇号应该放在“grownups’”中“P”和“S”之间：
A grownups' advantage is that he has already experienced disappointment.
如果是名词的复数形式，你只需在其复数形式之后加撇号来表示所有格：
We borrowed our parents' car.
当某物为两个或两个以上的人共有时，“’s”要加在最后一个名词的后面(John and Jack's room)。当表示各自所有时，你就需要像下例中那样加以指明：
Ian's and George's ambitions are very different from each other and from the ambitions of most ten-year-old boys.
物主代词不需要加撇号。
His, hers, its, ours, yours, theirs,和whose本身就是表示所有关系的代词，因此不需要再加撇号。这个句子是个错误的句子：
Each art room has it's own wash area.
It's的含义是 it is。
不要用撇号来表示名词的复数形式。
撇号表示的是所有格，不表示名词的复数形式。这个句子是错的：
Vendor's at the street fair sold animal balloon's and hotdog's.
这句话应该改为：
Vendors at the street fair sold animal balloons and hotdogs.
大部分的语法书指出数词，字母和缩略词也不能用撇号表示他们的复数形式。
下面几句是正确的例子：
The skater enthralled us with her perfectly executed figure 8s.
My son's Is look like Js when he writes in cursive.
My father earned two PhDs, one in biology and the other in chemistry.
仔细阅读你所用的撇号，看看你的用法是否正确。
When you want to show ownership, use an apostrophe and an "s." The apostrophe is efficient. For example you don't need to write:
the dogs owned by our neighbor
when you can write:
our neighbor's dogs.
When a noun ends in "s" and the addition of 's makes the word sound odd, some writers add only an apostrophe, as in this example:
James' friends
In reviewing your work, be certain that you have used apostrophes where you need them. How should this sentence be corrected?
A persons instincts are sometimes correct.
Writers sometimes put the apostrophe in the wrong place. For example, in the following sentence the apostrophe should really be between the "p" and the "s" in grownup:
A grownups' advantage is that he has already experienced disappointment.
You will only use a possessive word ending with an apostrophe if it is a plural word:
We borrowed our parents' car.
When two or more people share ownership, you use an apostrophe and "s" on the last noun (John and Jack's room). When each person has separate ownership, you need to indicate that, as in this example:
Ian's and George's ambitions are very different from each other and from the ambitions of most ten-year-old boys.
Possessive pronouns don't take an apostrophe.
His, hers, its, ours, yours, theirs, and whose are pronouns that already convey possession, so don't add an apostrophe to them. This sentence is wrong:
Each art room has it's own wash area.
It's means: it is.
Don't use an apostrophe when you want to make a noun plural.
An apostrophe shows possession not the plural of a noun. This sentence is wrong:
Vendor's at the street fair sold animal balloon's and hotdog's.
This sentence should be corrected to look like this:
Vendors at the street fair sold animal balloons and hotdogs.
Most stylebooks now indicate that numbers, letters, and abbreviations also do not need an apostrophe to show plural. Here are some correct examples:
The skater enthralled us with her perfectly executed figure 8s.
My son's Is look like Js when he writes in cursive.
My father earned two PhDs, one in biology and the other in chemistry.
Proofread all the words where you have used an apostrophe to check whether you used it correctly.