horse, hoarse

Horse or horse means the four-legged animal that cowboys ride--
At the end of the movie, he rode his horse into the sunset.
After cars were invented, some people didn't ride horses anymore.

Hoarse or hoarse ( rhymes with horse ) means having a sore throat that makes one's voice raspy--
The speaker talked so long that he became hoarse.
They were hoarse from cheering at the ball game.

Now that you know that, you can say--
"He yelled 'my kingdom for a horse' so many times that he became hoarse."

Note--"hoar" is a different word, meaning something like frost, that  settles on the ground when it is cold--
The sight of the hoar on the fields made him shiver.
"Hoary" may mean covered with frost, or with gray or white hair--
The old man was hoary with age.