There are still many problems ______ before we are ready for a long stay on the Moon.
#88396
A
solving
B
solved
C
being solved
D
to be solved
推荐题目
During the tourist season, there are many people wandering in this city to see the old castles_____ in the sixteenth century.
#98595
A
to be built
B
being built
C
having been built
D
built
(2013·湖南，25)The sun began to rise in the sky，________the mountain in golden light.
#89229
A
bathed
B
bathing
C
to have bathed
D
have bathed
When the fire broke out, Mary didn't know ___.
#97806
A
what to do
B
what do
C
to do what
D
what thing to do
As we all know, it was _____ that resulted in the terrible car accident.
#98204
A
because of her carelessness
B
her being careless
C
because she was careless
D
she was so careless
Although _____of danger, tourists can't help taking photos near the cliff （悬崖） ．
#90016
A
having warned
B
warned
C
warning
D
to be warned