This isn't actually correct. A semi automatic will automatically eject the spent cartridge and load the next. If you don't "pull it (the trigger) again" it will still eject the spent casing. The automated part of the semi automatic is the cycling of the action, that the shooter doesn't have to manually eject and chamber another round. #3 is true, what am I missing ?
When the trigger of a semi-automatic firearm is pulled, it will fire once until pulled again.
Semi-automatic means that every time the trigger is pulled, it will fire once until pulled again after which it will automatically eject the spent cartridge and chamber the next one. It can then be fired again.
Fully-automatic firearms will eject and chamber as long as the trigger is pulled and held. Machineguns, submachineguns and any gun that fires a burst (firing a certain number of rounds per pull) are considered full-automatic.
