A:(0,2)
B:(0,1)∪(1,2)
C:(0,2
D:(0,1)∪(1,2
—Where are the ____ from?
—They are from China.
使用催化净化装置,可降低汽车尾气中CO和NO的排放,其反应原理为2NO+2CO□+2CO2,则□内应填( )
_____ you know English is important, you should learn it well.