______ it rain tomorrow, we would have to put off the visit to the Water Cube.
#80202
A
Should
B
Could
C
Had
D
Were
推荐题目
_________, the forest fire would have been discovered much earlier.
#83151
A
But for their care
B
If they were careful
C
Without their care
D
Had they been more careful
—Do you often go to the gym? You look fit．—On the contrary, seldom ____ in my spare time．
#82464
A
I work out
B
did I work out
C
I worked out
D
do I work out
The research is so designed that once ____ nothing can be done to change it.
#84058
A
begins
B
having begun
C
beginning
D
begun