Jim had just stepped out of the bathroom and was busy drying himself with a towel ______ he heard the steps.
This new-type machine____________ little room.
--You don't look so well, Mary. What's the matter with you? --Why?___________.
China has hundreds of islands, ___________ is Taiwan Island.
You must have waited here for a long time ,___________you?
Nearly________ of the surface of our planet is covered by water.