It’s necessary for human beings to breath _______ and plants can produce it.
#17259
A
CO2
B
H2
C
O2
D
N2
推荐题目
In ancient China, Huabiao was set up to encourage people to carve _______ on.
#17258
A
their names
B
the good things
C
the Emperors’ names
D
their suggestions
You are _______ twenty—two . You should have more test .
#17293
A
not ---any longer
B
no longer
C
not---any more
D
no more
—We can see the signin the public places. What does it mean?—It means________.
#17198
A
NO PHOTOS
B
NO FISHING
C
NO PARKING
D
NO SMOKING