The World Health Organization gave a warning to the public without any ______when the virus of H1N1 hit Mexico in April, 2009.
_______ about the universe up till now.
So badly ______ in the accident that he was sent to a hospital.
Not until Mr. Smith came to China ______what kind of a country she is from.
It may rain, but I shall go out _____.
She is _____ out on Sundays.