Was it at the Olympic Games ______ were held this year ______ Liu Xiang got a metal?
It might have been John _____ bought a present for Mary yesterday.
What is it _____ his daughter needs most?
Who was it _____ saved the drowning girl?
“How was ______ they discovered the entrance to the underground palace?” “Totally by chance.”
When was _____ that the general manager left for Japan?