What is the plural of a two-word proper name? E. g.,

+ There are many "Toms Smith" in the Manhattan phone book.

+ There are many "Tom Smiths" in the Manhattan phone book.

There are many "Tom Smiths" in the Manhattan phone book.

Explanation:

Although using plural for proper nouns may seem strange since it's not common in everyday speech, there is an established set of rules that deals with it. When we talk about two-word personal proper nouns, the most important rules are as follows:

- only the second word is used to make plural form

- in most cases adding "s" is the correct way

- if proper nouns end with "s" or "z" then we need to add "es" to make proper plural form (one Patty Mills, three Patty Millses)

So, with this in mind, the correct answer would be adding "s" on the second word (Tom Smiths)