The new film Master and Commander gives a splendid opportunity to do just that. In the sequence I've seen, Russell Crowe gives the order "Fire! " Now if anyone had shouted that on one of those wooden ships in the Napoleonic wars you would have gone racing for a bucket of water to stop the fire reaching the powder magazine, or it would have been "Goodnight, Trafalgar".
To avoid confusion, the Royal Navy order to let off a cannon was (and still is ) "Shoot!"
History teachers should use that to show kids how careful we must be when using even the most lavishly-produced films as sources.
Everyone else should feel free to show off and annoy everybody around them.
RA Vant 13 Back Lane Holmfirth Huddersfield