principle software engineeting course

use ( Use Case Diagram ) to do this :

Use case diagram:

a web application to share photos. A user must be logged in successfully. When the user want to upload a photo he/she chooses a file from the computer and give a name to the photo theyre also give the option to add keywords to it (tags). After uploading the photo an email is sent to a moderator and an on screen message is shown notifying them of the email being sent. The moderator must be logged in successfully in order to view the list of photos waiting to be approved. The moderator can approve the photos