It’s not easy for the expert to ______ pig flu.in humans from regular human seasonal influenza.

Why ? Where’s the key to the meeting room? —-Dear me! You ______it in the taxi!

Dr. Green, as well as his wife and children, ______visit Beijing this winter.

When and where to build the new factory ___ ________ yet

Will you read me a story, Mummy? — OK. You _____ have one if you go to bed as soon as possible. [ ]