Khan Academy
Khan Academy: Meet the Apostrophe
Apostrophes have many important uses in the English language, and this exercise will give you an introduction to those uses!
Towson University
Towson University: Online Writing Support: Apostrophe
This entry explains and provides examples of when and how to use the apostrophe to show ownership and to form the plural of letters, numbers, and signs used as words. It also explains when not to use apostrophes such as with the pronoun...
Capital Community College Foundation
Guide to Grammar and Writing: The Apostrophe
What is an apostrophe? Where are apostrophes found in writing? Use this website to learn more about these crazy little punctuation marks.
Sophia Learning
Sophia: Apostrophes: Lesson 13
This lesson introduces apostrophes and how they are used. It is 13 of 13 in the series titled "Apostrophes."
Sophia Learning
Sophia: Apostrophes: Lesson 9
This lesson introduces apostrophes and how they are used. It is 9 of 13 in the series titled "Apostrophes."
Online Writing Lab at Purdue University
Purdue University Owl: Possessive Pronoun and Apostrophe
This Purdue Online Writing Lab article explains the three uses of the apostrophe.
English Plus+
Grammar Slammer's Apostrophes Showing Possession
This site discusses the correct and incorrect usage of apostrophes to show possession and examples are provided. Note that links are provided at the bottom of the page for other specific uses of the apostrophe.
Sophia Learning
Sophia: Apostrophe Guidelines for Possessives
This lesson explains the use of apostrophes to form possessives.
English Plus+
Apostrophes With Possessives of More Than One Owner
When to use the apostrophe when more than one person shares the same item, and when similar items are owned individually by different owners. Examples are provided.
Khan Academy
Khan Academy: Introduction to the Possessive
Learn to use apostrophes to indicate possession, or ownership -- and when not to use them.
Khan Academy
Khan Academy: Advanced (Plural) Possession
Possessive plurals have a complicated relationship with apostrophes, but this exercise is here to help you understand it!