According to Martin (1970: 59), the job of someone who explains something to someone "is to fill in the gap between his audience's knowledge or beliefs about some phenomena and what he takes to be the actual state of affairs". From Martin's point of view one can argue that what counts is causing the audience to know or believe something of which they were previously ignorant. At the extreme end, explanation has been thought of in a restricted sense as a special type of telling which goes beyond description. Pavitt (2000) is of the view that answering the question "why" is an explanation. In another debate, Trevor (2002) argues that for an explanation to be good the explanation must be valid in the context in which it is used and must also be understood by the listener. This implies that for an explanation to be understood, it should be clearly presented by the explainer.