Similes: Learning English through Colloquialisms

http://www.englishexercises.org/makeagame/viewgame.asp?id=5642

My friend is blind as a bat but her brother is mad as a hatter. These comparisons which do not really compare but illustrate (vaguely) some aspect of a person or thing or situation are called similes. Every language has this capacity, I imagine, and my students are often quick to find equivalent expressions in their own language. For example, if you say someone is "thin as a rake" (as in the image) in English, you could translate it into Spanish as "está hecho un pílgano." But, as the link indicates, be careful with how you use similes. They are useful for informal or friendly situations, for general conversation, but not always appropriate for more formal matters.