________ is known to us all is that the 16th Asian Games will be held in Guangzhou in 2010.
We _________ our breakfast when an old man came to the door.
_________with the size of the whole earth,the highest mountain does not seem high at all.
The bridge was named_________ the hero who gave his life for the cause of the people.
.The harder you_________,the better progress you_________.
When_________why he was late, he made no answer.