1. Do many workers use computers at your office? 2. People use professional computers in concrete professional sphere. 3. He hadn’t repaired the printer by the time his boss arrived. 4. Did they explain you how to solve this problem on a computer? 5. They developed C++ from the C language. 6. They use a printer to print the computer output on paper. 7. The user saw the computer in action. 8. We are redesigning our website at the moment. 9. When did Popov invent the radio? 10. You can launch the desired program or document by double-clicking the icon. 11. Kate is choosing a new scanner at the moment. 12. They made this processor in South Korea. 13. A lot of children use computers nowadays. 14. Who developed the first personal computer? 15. You must follow these instructions very carefully.