Personal computers ______ in 1976. It has changed the whole world.
A．have invented B．were invented
C．is invented D．invented
—Terra, you shouldn’t be so ______. You always leave your things everywhere.
—Sorry, mom. I’ll put them away soon.
A．terrified B．cheerful
C．frightened D．careless
By the time I got home, Gina and her sister ______ their project already.
A．finished B．have finished
C．had finished D．will finish
—I think you can ______ money by yourself to buy a present for your mother.
—OK. I’ll try. I’ll not let a penny waste.
A．spend B．save C．cost D．leave
—I think the man over there must be Bob.
—It ______ be him. He has gone to Paris.
A．can’t B．can C．may not D．mustn’t
Everyone knows that Diaoyu Island belongs ______ China.
A．with B．to C．in D．of
