一Excuse me.I want to buy some stamps,but I can’t find a post office.一I know________ nearby.Come on,I’II show you.
It's ______ he helped you that I'm ready to help him.
______ you ever have any trouble, let me know.
______, the library was closed.
Tom and Jack went ______ they could find work.
He wrote his first novel ______ studying in a university.