Is it Morris or Morris's?
When two or more people own something, you only put the possessive on the last noun. Innocent: Jenna and Morris's dogs were friendly. When Jenna owns her dogs separately from Morris, use the possessive on both nouns. Innocent: Jenna's and Morris's dogs were friendly.
Names are proper nouns, which become plurals the same way that other nouns do: add the letter -s for most names (“the Johnsons,” “the Websters”) or add -es if the name ends in s or z (“the Joneses,” “the Martinezes”).
When it comes to showing possession, to make most surnames possessive, simply add an apostrophe and an “s.” Mr. Smith's car was repossessed. For showing family possession with surnames that are plural and possessive, make the name plural first by adding an “s” and then add an apostrophe to make them possessive.
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With names, apostrophes are for possessives.
- The Joneses' dinner was a success.
- The Foxes' house was beautiful.
- The Alvarezes' grandmother was delighted.
- The Churches' singing was heavenly.
- The Ashes' train derailed in the mountains.
“Morris.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/morris.
The rules for pluralization are simple: Use an -s if your name ends with a vowel or a voiced consonant.
The Associated Press Stylebook recommends just an apostrophe: It's Tennessee Williams' best play. But most other authorities endorse 's: Williams's. Williams's means “belonging to Williams.” It is not the plural form of Williams. People's names become plural the way most other words do.
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. Hence: the boss' sister.
Jones = Mr. Jones's. Some people favor adding only an apostrophe to a singular noun ending in s, but if you follow the rule, you can't be wrong. If a plural noun does not end in an s, you must make it possessive by adding an apostrophe and an s: women's; children's.
All you need is an “s” at the end of the name (Smiths, Johnsons). If you have trouble remembering whether the apostrophe is necessary, think of your message. For instance, if you mean to say, “The Smiths live here,” then you don't need the apostrophe on the sign or that sentence.
Is it Thomas or Thomas's?
So a safe solution is to treat singular nouns ending in S the same way you treat singulars nouns not ending in S: Form the possessive with an apostrophe and an S. Thomas's house. The important thing to remember is that Thomas is singular.
According to English style guides, singular possessives are formed with –'s and plurals with just an apostrophe, so the possessive of the singular Jones is Jones's and of the plural Joneses is Joneses'.

If you want it boiled down to something simpler, remember this one thing: NO APOSTROPHES. Got it? NO APOSTROPHES. Not in your own name, either: sign it “With warm holiday wishes from the Jameses,” not “the James's” or “the James' ” or “the Jameses',” or, heaven help us, “The Jame's.” Why?
If the compound noun (e.g., brother-in-law) is to be made plural, form the plural first (brothers-in-law), and then use the apostrophe + s. Rule 4a. If two people possess the same item, put the apostrophe + s after the second name only. Example: Cesar and Maribel's home is constructed of redwood.
The spelling Chris's, with an additional S after the apostrophe, is a more common way to write the possessive form of Chris. Most style guides, such as the Chicago Manual of Style, recommend that you use an apostrophe and an S to create the possessive form of a singular noun.
To form the possessive of a singular noun that ends in an “s” sound, be guided by the way you pronounce the word: (a) if a new syllable is formed in the pronunciation of the possessive, add an apostrophe plus “s,” e.g., Mr. Morris's eyeglasses; Miss Knox's hairdo; Mrs. Lopez's term paper…
Additionally the name Morris is of Anglo-Norman origin deriving from the "de Marisco" line (meaning "of the marsh" in modern English). In some instances the surnames Morris has been seen to derive from Morres, which is the plural topographical name for a "family living on the Morre" (moors).
First, make the noun Williams into a plural: Williamses. Then add the possessive apostrophe according to the rules that gave us “the cats' tails.” That gives us “We had dinner at the Williamses' house last year.”
Compound Words or Group Words
To make compound words or a group of words possessive, add an apostrophe and an "s" to only the last word. Ex: Singular: The chairman of the board's decision was final. Ex: Plural: The daughters-in-law's children argue about everything.
The last name “Johnson” becomes “The Johnsons”. “Clark” becomes “The Clarks”. And “Edwards” becomes “The Edwardses”.
When a last name ends in s possessive?
If a proper name ends with an s, you can add just the apostrophe or an apostrophe and an s. See the examples below for an illustration of this type of possessive noun. You're sitting in Chris' chair. You're sitting in Chris's chair.
Remember: the only time you add an apostrophe to a last name is if you are making your last name possessive. For example, "That is the Gamels' house on the corner."
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.)
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.
Use 's for the possessive of singular nouns that end in s:
Charles's books, Dickens's novels, actress's script. Note: If a singular noun ending in s is followed by a word beginning with s, use only the apostrophe, not the 's. For example, Charles' shirt.
This is Travis's house. (correct and sounds better) This is Travis' house. (correct but awkward-sounding)
If your last name is Johnson and you want to send a card from your family, simply add an "s": The Johnsons ("Merry Christmas from the Johnsons!"). Only use an apostrophe when you want to make a name possessive. ("From The Smith's" is always wrong, but "The party is at the Smiths' house" is correct.)
The only time you would add the apostrophe is for possession: Welcome to Kerry Smith's Home or Cole and Kerry Smiths' Home. So if we're making signs, for instance, we'd say: Welcome to the Smiths, Welcome to the McBrides, Welcome to the Davises, Welcome to the Joneses, Welcome to the Hesses.
Use an apostrophe when showing possession
When showing possession, add apostrophe “s” ('s) to the “owner” word. If the plural of the word is formed by adding an "s" (for example, cats), place the apostrophe after the "s" (see guideline #3 below).
Compound Words or Group Words
To make compound words or a group of words possessive, add an apostrophe and an "s" to only the last word. Ex: Singular: The chairman of the board's decision was final. Ex: Plural: The daughters-in-law's children argue about everything.
Is it Johnsons or Johnson's?
That's because the apostrophe before the “s” indicates ownership or possession when that's not the sign's intent. All you need is an “s” at the end of the name (Smiths, Johnsons). If you have trouble remembering whether the apostrophe is necessary, think of your message.
Normally, an apostrophe and then an "s" is used to show ownership. For example, my name as a possessive noun is Parzival's. When the noun ends in s, we put the apostrophe behind the s but don't add another one. So for Francis it's Francis' and not Francis's.
Remember: the only time you add an apostrophe to a last name is if you are making your last name possessive. For example, "That is the Gamels' house on the corner." Thanks for reading!
If the name ends in s, z, ch, or sh, you need to add es. That means the Davis family becomes the Davises, the French family becomes the Frenches, the Hernandez family becomes the Hernandezes, and the Glaves family becomes the Glaveses.