He may come, but I’m not sure _______ that.
----Your monitor is never late for school, is he?--- ______.He always comes to school earlier than others.
---Are Mr. and Mrs. Wang living alone in the house? ---Yes, they have three sons, but ______ of them live in their own houses.
--- I hear that Hu Jintao will come to Nantong because the Sutong Bridge is open to traffic soon.--- Do you know _______?
All the information except these two pieces _____ writing the article.
What is the best way you think of ______ the environment?