To keep safe,everyone________to wear a seat belt in the car.
Would you mind closing the window to stop the wind _______ the papers away.
—David has made great progress recently. —________, and ________.
Mary with her sisters ________ Chinese in China.
Students should do everything they can ________ their study.
—I don’t know if Dr. White _______ to the party next week? —I think he will come if he ________ free.