Administrators and Project Managers can track time for other people in the account, so long as those people have been invited and have a licensed seat.
How to track time for other people:
Click on their profile from your company page (click on your company name on the upper left) to see a list of all the people in your account OR
Search for the person using our search bar (upper right)
If you are an Administrator or Project Manager in your account and nothing happens when you click on their timesheet, that user is most-likely not a licensed user. Visit Account Settings > People to see a list of your Licensed Users and Managed Resources. If the person is a Licensed User, you can confirm or adjust the time on the timesheet. If they are a Managed Resource, you cannot track time on their behalf.