you report it. Its the right thing to do!
The first thing to do - is raise the alarm. Whether that's activating a fire alarm - or reporting an accident to a tutor.
inform them
The first 'thing' anyone sees when approaching Antarctica is ice.
It depends on what sort of accident you're talking about. In a car accident, for example, you'd want to turn off your car first thing in case of fire.
inform them
Report it to someone in authority.
Check to see if there are any casulties
in my opinion you should tell the teacher immediately
stop and give whatever assistance is necessary
I recently saw a commercial from Allstate and they have an accident forgiveness program.
An eyewitness.