Apostrophes are great at standing in for missing letters, allowing us to shorten words. Paige and David discuss contractions and the Principle of Least Effort.

Practice this yourself on Khan Academy right now: https://www.khanacademy.org/the-apostrophe/e/introduction-to-contractions

Watch the next lesson: https://www.khanacademy.org/humanities/grammar/punctuation/the-apostrophe/v/introduction-to-the-possessive-the-apostrophe-punctuation-khan-academy

Missed the previous lesson? Watch here: https://www.khanacademy.org/humanities/grammar/punctuation/the-apostrophe/v/introduction-to-the-apostrophe-the-apostrophe-punctuation-khan-academy

Punctuation on Khan Academy: Punctuation is the collection of squiggles, dots, and lines that we use to separate sentences and their parts. Is a question mark punctuation? Yes, and so is an exclamation point!

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