The Rhyming Game

I was playing a game with Pete the other day. Basically, you sing this song to the tune of "Here We Go Round the Mulberry Bush":

I know some words that rhyme with car,
rhyme with car,
rhyme with car.
I know some words that rhyme with car,
Do you know some too?

Then Pete says words that rhyme with car, and then you do other words.

Then I said "ok, Pete, it's your turn". He looks frantically around the room to think of a word, then sings:

I know some words that rhyme with picture,
rhyme with picture,rhyme with picture.
I know some words that rhyme with picture,
Do you know some too?

I thought for a moment and said "sorry Pete, there are no words that rhyme with picture".

He thinks for a second and says "what about mixture?"