This is the 15449th most frequent Russian word.
предложении
"Предложении" means "sentence" or "proposal" depending on context.
Here, 'предложении' is used to mean 'sentence', referring to a linguistic unit.
Он упомянул это в своем предложении.
He mentioned this in his sentence.
In this sentence, 'предложении' refers to 'proposal', indicating a suggestion or offer.
Она согласилась с его предложением.
She agreed with his proposal.
Once again, 'предложении' is referring to 'sentence', specifically the one being discussed.