The phrase "activities someone have completed" means the tasks or things that someone has finished or done.
Sentences with «activities someone have completed»
Whether you have a degree or not, you will need to demonstrate an interest in fixing technical problems, either through previous work experience or activities you have completed in your own time. (targetjobs.co.uk)
It will track how many minutes of brisk activity you've completed for the day. (canadianbusiness.com)
A printable activity tracker is also included in the packet for students to keep track of how many activities they've completed! (tes.com)