—I wonder if you could go with me to the supermarket.
—Sorry. I _______ my experiment report all the morning and haven’t finished yet.
A.write B.was writing
C.have written D.have been writing
_______ a small number of Australians are bitten by spiders each year, most recover without any medical treatment.
A.While B.Unless C.When D.Because
This morning I saw an old friend of mine in the street by ______.
A.event B.accident C.affair D.matter
Everyone should _______________ the environment.
A.make a contribution to protect B.make contribution to protecting
C.contribute in protecting D.make contributions to protecting
—Listen, Lily is playing the piano!
—Wow, how sweet the music ______!
A.is heard B.hears C.is sounding D.sounds
________ tomorrow, I would take a bus to school.
A.If it rains B.If it was to rain
C.Should it rain D.Rained it