Everything is full of yellow dust because of the sandstorm（沙尘暴）.！

There ________ some beef on the table.

Why do youthink ______ — He could______ for exercise.

Unfortunately, when I dropped in, Doctor Li _____ for Beijing to join in the fight again H1N1, so we only had time for a few words

professor was asked to write anarticle for the newspaper, ___________about the left-behind children in thecountryside