It’s not easy for the expert to ______ pig flu. in humans from regular human seasonal influenza.
I really feel like ______a talk with Daniel about her lessons but don’t know how to pick it up.
The reason for his success is ______ he worked very hard.
I’m really tired _______ Tom.. He had me _________ for two hours in the rain.
Those experienced doctors in our country _______the meeting in order to find out the real_______ of bird flu(禽流感).
I shall never forget the days_________ I lived with my parents as a child, _________ has a great effect on my life.