用方框内所给词的适当形式填空。每词限用一次。

Which city is _________, Beijing or Shanghai?
Let’s do what we can ________ those homeless children.
Of all the ways to travel, I think going by train is the_________.
It’s a good idea to practise _________ English in and out of class.
Mo Yan won the Nobel Prize for literature _________ and becomes famous around the world.