Cron import has lines that are highlighted in yellow. What does that mean?

Cron import has lines that are highlighted in yellow.  What does that mean?

Anything after a % is feed as standard input to the command in front of it and cannot be scheduled from the cron import and will need to be edited. 

A Schedule that has @reboot cannot be scheduled because we have no way to schedule a job at reboot.  The job will be created and will run, but nothing will happen.