Name: __________________________________ Date: ______________________ English Language In some countries, a machine known as a lie detector is used to ______________ in criminal investigation. The lie detector is used to determine ________ the person involved in the crime is telling the truth or _________________. How does such a machine work ? When a person ___________ an untruth, certain body reactions may _____________ . For example, his heart may _______ faster and his face may flush. His blood pressure may ______ rise and his breathing may ______ quicker. It is the ____________________ of the lie detector to record these reactions. Normally, the machine _______________ record reactions which the subject has no control __________ , such as his blood pressure, respiration or pulse. How reliable ______ these machines? Some countries do not use lie detectors _______ they feel that these machines are not totally reliable. in fact, the success ____________ of the lie detector depends greatly ______ the sensitivity of the machine. The ability of the person ___________ the test is also very important. The examiner must know specifically ________________ kinds of questions to ask his subjects. The examiner would usually familiarize himself _____________ the details of the case first. He then asks his subjects ________________ that are totally unrelated __________________ the case. The answers to these questions would ___________________ the examiner gauge what _____________ 'normal' reactions of the subject _____________ . After this, the examiner would ask questions of _____________________________ kinds -- those that are important to the case and those which have nothing to ______________________________ with the case at all.