How to unlock exercises?

1. After completing all exercises of a week, you might want to proceed to the exercises in the next week. You will find that the exercises of upcoming weeks are all locked.

2. To unlock the exercises, you will firstly need to close the Workbook tab and stay on the Coursera page.

3. On Coursera, switch to the target week you would like to study, and find an item with "Ungraded External Tool."

4. Click that item and open the tool. All exercises of that week are now unlocked.

5. The same process applies to other weekly exercises as well.