Apostrophe Use, Lesson Number 1

From the Chicago Manual of Style:

Possessives and Attributives
Q. How does one make the following names possessive (and all first names that end in “s”)? James, Iris.
A. Chicago style adds an apostrophe and an s: James’s, Iris’s. But please see CMOS 7.17–23 for more examples and exceptions to the rule.

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