Carbon dioxide ___ from burning fuels is the most common of the so-called greenhouse gases.
#4678
A
producing
B
having been produced
C
to be produced
D
produced
推荐题目
There is no perfect person, some people have made _____success of themselves in spite of what would appear to be ______ weakness in their professions.
#4593
A
/, a
B
a, /
C
a, a
D
/, /
Though we found _____difficult to avoid economic and financial crisis, we must take measures to reduce its negative impact.
#4854
A
it
B
one
C
that
D
how
.—What do you think made Jenny so happy?—_________ a ticket to the opening ceremony of the 29th Olympic Games.
#4770
A
To win
B
Won
C
Winning
D
Win
To understand the grammar of the sentence,you must break it______ into parts.
#4913
A
down
B
up
C
off
D
out