Isthathispen_____thelostandfoundcase?[ ]

About ________ of the workers in the factory were born in the ___________.

Congratulations! Among the best pictures in the competition, I found _________. When did you draw it?—During the trip to the Yellow Mountain _________ May.

When are you going to Hainan?—I am going there ___ June 8, 2011.[ ]

The teachers ________ on the blackboard with chalk in the future.