Unit II. Computer systems lesson Theme: Living with computers

A PPENDIX 2. GLOSSARY

APPENDIX 3. VIDEO
A CPU.

Work in pairs. Watch a video. Make a list of CPU components and give their functions

CPU component	Its function

APPENDIX 4. LANGUAGE.
Passive Voice (Video)


Complete the sentence with proper Passive form.

1. 
   After the earthquake, aid was sent to the people of Haiti. (sent)
   
2. 
   The electricity was cut off because the bill hadn’t been paid. (not pay)
   

1. 
   Penicillin ______ by Alexander Fleming in 1928. (discover)
   
2. 
   Statements ______ from all the witnesses at this moment. (take)
   
3. 
   Whales ______ by an international ban on whaling. (must protect)
   
4. 
   Both weddings _______ by Good Taste. (cater)
   
5. 
   A Picasso ____ from the Metropolitan Museum of Art.(steal)
   
6. 
   ____ this washing machine ______in Germany? (make)
   
7. 
   Tea _____ in China. (grow)
   
8. 
   The fax _____ until tomorrow morning. (not send)
   
9. 
   The soundtrack of a movie _____ always _____ after the filming is finished. (is/add)
   

APPENDIX 5. READING.
A The processor
The processor, also called the CPU or central processing unit, is the brain of your computer. In PCs, it is built into a single chip- a small piece of silicon with a complex electrical circuit, called an integrated circuit- that executes instructions and coordinates the activities of all the other units.
Three typical parts are:

• 
  the control unit, which examines instructions from memory and executes them;
  
• 
  the arithmetic and logic unit (ALU), which performs arithmetic and logical operations;
  
• 
  the registers, high-speed units of memory used to store and control data.
  

The speed of processor is measured in gigahertz (GHz). Thus, a CPU running at 4 GHz can make about four thousand million calculations a second. An internal clock sends out signals at fixed intervals to measure and synchronize the flow of data.
B A motherboard
The main circuit board is known as a motherboard. This contains the CPU, the memory chips, expansion slots and controllers for peripherals, connected by internal buses, or paths, that carry electronic signals. For example, the front side bus carries all data that passes from the CPU to other devices.
Expansion slots allow you to install expansion cards which add features like sound, memory and network capabilities.