sophialaw81

問個想不透的問題
have been required in all new cars in Donia since 1993, and as a result, nitrogen dioxide emissions have been significantly reduced throughout most of the country.  

1993 安裝後...有短暫的滅少...

那搭配E .. 又說      too short for the catalytic converter to reach its effective

感覺二句中有矛盾...一個是有安裝後有減少...E是  trip is too short以致於沒減少
(最大疑問在這裡)


throughout most of the country....整個country 降低......而非單指D城.
如果是這原因,我就了解了