Robin L. Simmons
Grammar Bytes: Word Choice: Exercise 10: Whose and Who's
Test your understanding of the words "whose and "who's" by typing the word that best completes each of the twenty sentences. Immediate feedback on answers is provided and a percentage score is tallied throughout the quiz.
Robin L. Simmons
Grammar Bytes: Word Choice: Exercise 14: Its and It's
Test your understanding of the words "its" and "it's" by typing the word that best completes each of the twenty sentences. Immediate feedback on answers is provided and a percentage score is tallied throughout the quiz.
PBS
Pbs Learning Media: Some Frequently Confused Words
Some words in English can look and sound similar, but have entirely different meanings. Keep an eye and ear out for them; beware of commonly confused words. [0:40]
Other
Ginger: Spelling Book: Confusing Words: Bi, Buy, By, Bye
Definitions and examples of the commonly confused homophones bi, buy, by, and bye.