The principle of cloze testing is based on the Gestalt theory of "closure" (closing gap in patterns subconsciously). Thus, cloze tests measure the reader's ability to decode"interrupted" or "mutilated" messages by making the most acceptable. Every nth word is deleted in a text (usually every fifth, sixth or seventh word). and students have to complete each gap in the text, using the most appropriate word. The followingis an extract from an advanced level close passage in which every seventh word has been deleted: