[2013·安徽卷] From space, the earth looks blue. This is ________ about seventyone percent of its surface is covered by water.
She finds ______ boring ______ at home.
______ for the free tickets, I would not have gone to the films so often.
He said, “_____ a long way to school. _____ a long way to go yet before we arrived.”
It’s the third time _____ arrived late this month.
Our classroom is very clean. Do you know who___cleaned it?