题目内容：

句子填空（共5分）

1.It’s very convenient to ____ _____ _____ _____ their families and friends by using mobile phones.

2.Some of them even waste precious time in class _______ _________ ___________. 

3.With the global warming getting worse, more people choose to live a low carbon life ______ ______ __________ _____ reducing greenhouse gases.

4.Only by_______ _______ ________, will we have fewer disasters and a safer earth. Let’s work together and fight for a better future.

5.Wash your clothes by hand______ _______ ______ __________ instead of using washing machines.