(Sorry it has been so long. It has been crazy busy lately.)
Rein and reign and rain all sound the same*, and they all have both noun and verb forms, so it’s easy to mix them up. Misusing rain (as in weather) is very rare, so I’ll focus on the other two.
Reins are what you use to steer horses. It’s also used in metaphorical expressions such as “We’ve got to rein in spending.”
Reign is what a king does. Note how similar it is to sovereign.
Trick to Remember
Reins are long and used for control.
A king may reign long or short.
*This makes them homophones, not homonyms, as I was told in grade school.
