PHP/MYSQL search, returning sentence(s) containing keywords

Hey Guys,
I have tried searching for this, as im sure ive seen something relevant but im struggling with search terms to really narrow things down!

Im using PHP to search an SQL database for keywords…no probs there, but I want to return…say the first sentence containing the word searched.

So if i had the following text:

“The quick brown fox jumpes over the lazy dog. Blah blah i like cake but i dont really like cheese”

And a users searches “cheese”, how could I just return “Blah blah i like cake but i dont really like cheese” ?