Metaphors are words and phrases that are not used in their literal meaning, but are used to describe something else.
'I have a lot on my plate', 'Sales really took off' and 'He's a real couch potato' are all metaphors.
In the classroom
Metaphors are a rich and enjoyable area of language for learners but also can be problematic, as their meaning is not immediately obvious. Activities that encourage the use and study of metaphors include; creative writing, classroom posters of metaphor groups, looking at euphemisms and finding L1 equivalents.