Reportedly on April 15, 2013 three people including a Chinese girl were killed in the Boston Marathon attacks when two bombs were _______, which shocked the whole world.
Without gravity, we _____ walk on the ground as freely as we do now.
Zhang Heng, one of _____ best-known Chinese astronomers, showed a strong interest in _____ astronomy as a child.
— Could I have another cup of coffee, Daddy? —_____ It will be hard for you to go to sleep tonight if you do.
With a report _____ about the accident, the policeman has to find some witnesses for help.
-The terrible accident might not have happened had the driver been more careful. --But he _____.