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小题1:It’s very convenient to ____ _____ _____ _____ their families and friends by using mobile phones.
小题2:Some of them even waste precious time in class _______ _________ ___________.
小题3:With the global warming getting worse, more people choose to live a low carbon life ______ ______ __________ _____ reducing greenhouse gases.
小题4:Only by_______ _______ ________, will we have fewer disasters and a safer earth. Let’s work together and fight for a better future.
小题5:Wash your clothes by hand______ _______ ______ __________ instead of using washing machines.
