This presentation discusses common words that are often confused because they look or sound similar. It provides definitions and examples for several pairs of words including: - Affect vs Effect: Affect is a verb and effect is usually a noun, though it can also be used as a verb. - Allusion vs Illusion: An allusion indirectly refers to something while an illusion is a false idea or perception of something. - Principal vs Principle: These two words are commonly mixed up though they have different meanings. The document aims to clarify the definitions and proper usages of similar-looking and -sounding words to avoid confusion. It asks questions at the end to check understanding and provides references for additional