Question: how many days a week can you work?
Answer: You can't work more than 48 hours a week on average - normally averaged over 17 weeks. This law is sometimes called the 'working time directive' or 'working time regulations'. You can choose to work more by opting out of the 48-hour week. If you're under 18, you can't work more than 8 hours a day or 40 hours a week.