Scientists are convinced___the positive effect of laughter___physical and mental health.()
My daughter, _________ all kinds of meat, would not like to eat any vegetable, which worries me a lot.
It was in the lab _____ was taken charge by Professor Wang ______ they did the experiment.
No one can avoid ______ by advertising; it is everywhere.
With all the audience ________, the speech began.
—Ken, why do you look so tired? —I _______ myself to the climate since I came here.