Plurals of letters, initials, abbreviations, and numbers Quick Use: Use apostrophe + s for single letters, and just an s for initials and abbreviations (which have more than one letter)> Either apostrophe + s or just an s words for numbers (2s, 3s, or 2's, 3's), but be consistent.
1s and threes are simply plurals. So no apostrophe is needed.
The Associated Press Stylebook says the correct way to write the possessive case of Chris is Chris', not Chris's. Other style guides, including the Chicago Manual of Style, say Chris's is correct. If there isn't a specific guidebook you need to follow, you can use either Chris' or Chris's.
The apostrophe has three uses: 1) to form possessive nouns; 2) to show the omission of letters; and 3) to indicate plurals of letters, numbers, and symbols. Do not use apostrophes to form possessive pronouns (i.e. his/her computer) or noun plurals that are not possessives.
Forming plural numbers is a lot easier than forming plural words. You simply add an “s” to numbers. The other key rule to remember is that you do not need to add an apostrophe before the “s.”
Rule to Remember
Numbers can be shortened by adding an apostrophe in place of the omitted number. An apostrophe and s are also used to form the plural of letters, numbers, signs, and words referring to words. Correct: The word Mississippi has many s's.
Apostrophes aren't typically used to create a plural. However, there are exceptions for forming plurals of numbers, abbreviations, and symbols. For instance, “there are two 7's in her number.”
The important thing to remember is that Thomas is singular. When you're talking about more than one, you first form that plural by adding -ES. One Thomas, two Thomases. Then, to note that something is owned by more than one Thomas, just take the plural and make it possessive: Thomases'.
When using a plural noun, the apostrophe goes after the s. For example: “The squirrels' nuts were hidden in several hollow trees throughout the forest.” When using a word that is pluralized without an s, add an s to the end of the word and place the apostrophe in front of it.
The possessive case of plural nouns that end in s is formed by adding an apostrophe: This is the boys' bedroom.
If your brother is named Chris and you have a friend named Chris, then you know two Chrises. First names aren't usually pluralized in conversation, but it is grammatically correct to do so. As to the form of Chrises, since the word ends in -s, the plural form is -es.
The possessive
Quick Use: Use an apostrophe + s for singular nouns (sea, sky), common nouns ending with s (tigress, mistress), and irregular plural nouns (women, children). Use only the apostrophe for proper nouns ending with s (Tess, Jesus, Texas) and regular plural nouns (cars, protestors).
There are some acceptable variations; however, you will never be wrong if you follow three simple rules. First, if your noun is singular, its possessive will always be on target if you add an apostrophe and an s: girl = girl's; town = town's; Jess = Jess's; Mr. Jones = Mr. Jones's.
threes - Simple English Wiktionary.
Most numbers use the suffix –th, except for 1 (first), 2 (second), and 3 (third). Numbers over 20 use the suffix of the last number, for example, the ordinal for 53 is fifty–third. Be careful of the numbers 1, 2, 3, 5, 8, 9, and 12, because their ordinals use irregular spelling.
A simple rule for using numbers in writing is that small numbers ranging from one to ten (or one to nine, depending on the style guide) should generally be spelled out. Larger numbers (i.e., above ten) are written as numerals.
Both James' and James's are grammatically correct.
Certain academic writing styles prefer one version over the other, but it doesn't matter which one you use in your regular, written English.
The double possessive, usually using both of and 's to demonstrate possession, is grammatical. While it is sometimes unnecessary, it can be helpful for differentiating when the possessive (or genitive) case is about association or ownership, such as in "a picture of my friend" vs. "a picture of my friend's."
Second, a name ending in s takes only an apostrophe if the possessive form is not pronounced with an extra s. Hence: Socrates' philosophy. Saint Saens' music.
For proper names like James, AP says, add an apostrophe only: He borrowed James' car. For generics like boss, add an apostrophe plus S: He borrowed the boss's car. But there's an exception: When the word that follows begins with an S, use an apostrophe only.
First, form your plural: You're visiting the Rosses. Then make it possessive: You're going to the Rosses' house. Remember, because this is plural, there's no dispute on how to make it possessive. Use just an apostrophe.
As a general rule, we never use an apostrophe in writing plural forms. (A plural form is one that denotes more than one of something.)
MPs, PCs and so on are plurals and do not take an apostrophe (unless, of course, the possessive form is required: the MP's home).
A common mistake people make is to include apostrophes when pluralizing a number or an abbreviation. Apostrophes are generally used in contractions and to indicate the possessive case, but they are not used to form plurals of numbers and abbreviations in APA Style.