I know Mr. Brown;we __ to each other at an international conference.
I like _____ in the spring when the weather is warm and everything begins to grow.
Is it to hold the 2010 World Exhibition _______ makes Shanghai the focus of the world?
We can never expect________bluer sky unless we create___________less polluted world.
Mike ______ have known the solutions to this problem, or he would have told us.
The confidence of the Chinese film makers ______ by Avatar, the release of______ has not only set a good example for the Chinese film industry but also embarrassed our directors, who lack professional ethics.