--- There is ________dark stain(污渍) on my coat. Who left it?---- It’s me, Dad. I did it just for ______ fun.
I will never forget the day _____ we worked together in London.
—That must have been a long trip.—Yeah, it us a whole week to get there.
To get a better grade, you should __________the notes again before the test.
Mary, I_____ John of his promise to help you.
I got this bicycle for______:My friend gave it to me when she bought a new one.