---What will you do if it _____ rain tomorrow? --- I’m not sure.
I hear Mr Brown lives here, but I’m not sure .
Since you are tired, you’ d better and have a good rest.
Don’t cut in line when you the bus at the bus stop.
--- do you take exercise? --- Twice a week.
--- Whose backpack is this? --- It be Mary’s. She is looking for hers.