Answer:
Step-by-step explanation:
We can't really do much with this until we know what the exact rule is. However here are 3 words and their sentences.
You: You should get to bed early tonight. Tomorrow is a big day.
Yew: This yew tree is 13 hundred years old. See below (left).
ewe: (a female sheep) This ewe has just been sheered. You would never know she is an Ewe. (See right photo below right). There was no intent to break copy write laws.)
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Their (possessive pronoun): That was their home before the fire.
There (adverb): It was over there.
They're (verb and pronoun): They're over at the park playing baseball.