By 3–5 years, children usually have difficulty using words correctly. Children experience many problems such as underextensions, taking a general word and applying it specifically (for example, 'cartoons' specifically for 'Mickey Mouse') and overextensions, taking a specific word and applying it too generally (example, 'ant' for any insect). However, children coin words to fill in for words not yet learned (for example, someone is a cooker rather than a chef because a child may not know what a chef is). Children can also understand metaphors.