二氧化硫排污费的收费标准为排放每千克二氧化硫收取排污费约( )。
A．0.2元
B．0.3元
C．0.4元
D．0.5元
参考答案：A
— I'm afraid I can't memorize so many new words in 2 days.
— _______. [ ]
A. Don't be afraid
B. You are clever
C. Not at all
D. Take your time
A．
B．
C．
D．
