What's done is done" says the confident lady macbeth after the play's opening scenes; "what's done cannot be undone" is her remorseful lament at the end. It is in precise analysis of such detail that a real contribution can be made to people's capacity to read and listen critically,and to resist being msnipulated by what is said the analysis of such language and its effects is known as Critical linguistics,or,when placed in a larger social context and seen as part of a process of social change, as Critical Discourse Analysis (CDA).