A. Read the following passage about the mouse's body and fill the gaps with the appropriate prepositions: The outer body of a mouse has a hard plastic shape that the user guides 1............ a flat surface. It's "tail" is the electrical cable leading 2............ of one end of the mouse and finishing 3.......... the connection with the CPU. At the tail end, one to three buttons are the external contacts 4.......... small electrical switches. The press 5........... a button closes the switch with a click; electrically, the circuit is closed, and the computer has received a command. A plastic hatch fits 6..... .a rubberized ball, exposing part 7 the ball which is held in place 8.......... a support wheel and two shafts. As the ball rolls 9............ a surface, one shaft turns 10.......... horizontal motion and the second responds to vertical motion. 11............ one end of each of the two shafts, a spoked wheel also turns. As these spokes rotate, infrared light signals 12..............a light-emitting diode (LED) flicker 13.............. the spokes and are intercepted by a light detector. The dark and light are translated 14. phototransistors 15.. .... electrical pulses that go to the interface integrated circuit (IC) 16........... the mouse. The pulses tell the IC that the ball has tracked left-right and up-down, and the IC instructs the cursor to move accordingly 17. the screen. The interface integrated circuit is mounted on the printed circuit board (PCB) that is the skeleton to which all the internal workings 18....... the mouse are attached. The integrated circuit, or computer chip, collects the information from the switches and the signals 19........... the phototransistors and sends a data stream 20. ..the computer. B. Highlight the most appropriate verb form for each sentence then justify your answer: 1. Adware ....... to track what you do online. a. Have been designed b. Is designed C. Would be designed *justification: 2. They ............. on this device for 5 years. a. Have been working b. Have worked c. Were working . weird! "justification: 3. Look! The computer a. Is being acting b. Acts c. is acting * justification: 4. The only thing that. faster than time is the progress of technology. a. Have been flying b. Is flying c. flies justification: 5. They great video cards and relatively stable software for gamers so far! a. Had built b. Built C. Have built *justification: our flexible friend 6. In the future, the mobile phone a. Will be b. Could be C. Might be *justification : 7. MorePhone .............. by scientists at the Human Media Lab in Canada. a. Was created b. Is created Page 2 sur 3 c. Have been created *justification: conventional 8. The quantum computer some of the problems that computers a. Will overcome / have plague b. Would overcome / have plagued C. May overcome / has plagued
