When did the Green family arrive ______ Shanghai? — They got there ______ the afternoon of May 2nd. [ ]

You must be very tired. Why not ___________a rest?

Shanghai is the city ______ the 2010 world Expo is held. –So it is a city____ most of us want to vist this summer.

Nobody knows the answer _______ this question.[ ]

How often do I need to feed the dog?——It___food everyday, or it will be hungry.