Astronomers and scientists think that a black hole is a region of space ______ which matter has fallen and _______ which nothing can escape.
—$1,500, but that’s my last offer. — OK. It’s a ____.
He left home in 1980 and has never come back ____.
— Hello, may I have an appointment with the doctor? — ____
— How about a game of chess? — ____
— I’m afraid I can’t finish the book this week. — ____.