There is ________ in his words.We should have atry.(2011·四川)

 —We want to finish the task ahead of time.—You have to _____________, if so.

China’s population is about       of the world’s.

Of all the books on the shelf,        is of any use for improving our practical skills of survival in the competitive world.

 Thanks to their hard work, the new bridge has been finished ________.