What is an example of an idiom?

An idiom is a phrase where the meaning cannot be understood from the individual words that make it up. "To break a leg" is a classic example of an idiom because it does not refer to the literal action of breaking a leg but is commonly used in theater to wish performers good luck before a show. This figurative language is prevalent in everyday expressions and highlights the cultural nuances of language.

In contrast, the other options represent more straightforward expressions where the meanings can be inferred from the individual words. "To read a book" and "to write clearly" convey direct actions, while "to see with your own eyes" states a literal condition that can be understood without ambiguity. These phrases do not carry the same idiomatic significance as "to break a leg."