— I think we should ask people to use public transport more often.— ______.
- ________ book is this? -- It's Mary's.
There ________ some tomatoes and milk in the box, but now there aren't any.
Our school is ________ a park and a big library.
Is this ________ bike? No. ________ is over there.
—Hello, may I speak to Mr Green , please? —Sorry. He ________ a meeting. Can you call him later?