化简﹣(﹣3)的结果是( )
A:3
B:-3
C:13
D:-13
化简求值:2(3x2﹣2x+1)﹣(5﹣2x2﹣7x),其中x=﹣1.
修改下边有毛病的句子。
①他愉快而高兴地告诉我,他去世后要捐赠所有完好的器官。
②遵从他的遗愿捐赠了他的眼睛。
③她的碧眼仍然闪耀着骄傲的光芒。
-You look so worried, what’s wrong?
-More and more people like me begin to worry about the ______ pollution after the haze (雾霾) appeared in Beijing and some other cities in China.