Complete the following sentences according to the passage. 1. A webcam is a video camera used to ____(发送) and display electronic pictures over Internet 2. A USB disk can easy ____(存储) and take data..3. A printer is a device to ____(打印)files. 4. A monitor is a computer____(显示) on which words or pictures can be shown. 5. Headphones are a pair of small ____(设备) through which you can listen to music from your computer 6. A computer keyboard is an input device from which you can____(输入)text or commands.