1. Who reads a book before he goes to bed?
1. What does Peter read before he goes to bed?
1. When does Peter read a book?
2. What device processes information with astonishing speed?
2. What do computers process with astonishing speed?
2. How fast do computers process information?
3. Where do they work twice a week?
3. How often do they work at the English language laboratory?
4. What do students know well?
4. How do students know grammar rules?
5. What often breaks down?
5. How often does the old car break down?