—Why does the lake smell terrible? —Because large quantities of water _____.
#93664
A
have polluted.
B
is being polluted.
C
has been polluted.
D
have been polluted.
推荐题目
If water becomes increasingly scarce in decades ______, water shortage will become a hot issue all over the world.
#91429
A
coming
B
having come
C
to come
D
to be coming
You know that widely reading helps ______ your knowledge so I can’t help _____ the housework every day.
#97977
A
an large, doing
B
to rich, to do
C
add, to
D
add to, doing
Greatly ______, the students made up their minds to work at English even harder.
#97645
A
inspiring
B
inspired
C
having inspired
D
to inspire
_______ in the queue for half an hour, Tom suddenly realized that he had left his wallet at home.
#93916
A
To wait
B
Have waited
C
Having waited
D
To have waited
When I entered the room, I found Mary ______ at the desk ______ her homework.
#95934
A
sat; doing
B
sitting; to do
C
seating; to do
D
seated; doing