The boy is often heard _____in the music room. He sings very well.
A．practice singing B．to practice singing C．practiced singing
Animals are our close friends. We are supposed _____ them.
A．to protect B．protecting C．protect
The Great Green Wall can stop the wind and sand_____ to the rich land in the south of China.
A．move B．to move C．from moving
—Excuse me. Could you tell me ____get to the nearest post office?
—Sorry, I am new here.
A．how can I B．how I could
C．how to D．what I can
He promised _____his old friend during his stay in Tianjin.
A．see B．seeing
C．saw D．to see
—What a heavy rain!
—So it is. I prefer ____ rather than ___on such a rainy day.
A．to go out; stay at home B．to stay at home; go out
C．going out; stay at home D．staying at home ; go out
