3D_Invisible Clues (2)

Read pages 14-21 and decide whether the sentences below are true or false. True Investigators use tweezers, tape or a scalpel to get evidence from the crime scene. The evidence collected is placed separately in different containers or bags. The superglue method is often used to show a faint fingerprint. False Investigators use hands to get evidence from the crime scene. The evidence collected is put together in a plastic bag. The superglue method is often used to show a faint shoe print. Suppose you were the chief investigator, how would you instruct your juniors to collect fingerprints and reveal latent fingerprints? We can use imperative sentences to give instructions (tell people to do something).→ We start an imperative sentence with a verb.→ We do not change the verb form. e.g. Simple instructions on how to replace a light bulb 1. Switch off the lights. 2. Remove the light bulb. 3. Screw in the new light bulb. 4. Turn the lights on. Fill in the blanks with a verb to form imperative sentences to give instructions. To collect fingerprints: (p.16-17)1. Dab the brush tip into fine powder.2. Dust a small amount of powder onto the surfaces with fingerprints.3. Keep brushing the surface with powder until you see the patterns of the fingerprint.4. Photograph the fingerprints.5. Cover the fingerprints with a transparent tape.6. Lift the fingerprints from the surface with the tape.To reveal latent fingerprints: (p.18-19)1. Place some superglue and the object that needs to be tested into a sealed container.2. Heat the superglue until it turns into a vapour.3. Wait until the vapour sticks to the oils and sweat on the fingerprints.4. Photograph the visible fingerprints. What should the investigator do when there are tyre prints and shoe prints in mud, sand, and soil at the crime scene? Use the passive voice to describe the making of an impression cast (p.20-21). The first one has been done for you as an example. 1. First, photographs are taken (take) by the investigators.2. Then the twigs or leaves on top of the tyre prints are removed (remove) carefully.3. A metal frame is placed (place) around the impression.4. After that, the impression is sprayed (spray) with a special spray to make it hard.5. Some plaster of powder is mixed (mix) with water in a bag.6. The mixture is poured (pour) onto the impression gently.7. Then, the mixture is left (leave) to dry for some time.8. Finally, the impression can be lifted (lift) by the investigator successfully. Complete the paragraph below with words from pages 22-26. When the evidence at the crime scene has been collected, investigators send them back to the laboratory for testing. There experts compare the fingerprints collected against the fingerprint database in order to identify the suspect. Match the words with the equipment shown in the pictures. gloves scalpel microscope tape brush digital camera