[单项选择]You should know better than ______ your little sister at home by herself.
A. to leave
B. leaving
C. to have left
D. left

[单项选择]You should know better than ______ your little sister at home by herself.
A. to leave
B. leaving
C. to have left
D. left

[单项选择]You should know better than ______ the risk of gambling.
A. to run
B. running
C. to have run
D. ran

[单项选择]If you took more than your share of the money, you should at once ______ by returning the extra amount.
A. come about
B. make amends
C. feel ashamed
D. get punished

[单项选择]It's no use__ me. I don't know more than you do.
A. in asking
B. asking
C. for me to ask
D. you ask

[单项选择]Once you get to know your mistakes, you should __________ them as soon as possible.
A. rectify
B. reclaim
C. refrain
D. reckon

[单项选择]

Humanity uses a little less than half the water available worldwide. Yet occurrences of shortages and droughts (干旱) are causing famine and distress in some areas, and industrial and agricultural by-products are polluting water supplies. Since the world’s population is expected to double in the next 50 years, many experts think we are on the edge of a widespread water crisis.
But that doesn’t have to be the outcome. Water shortages do not have to trouble the world -- if we start valuing water more than we have in the past. Just as we began to appreciate petroleum more after the 1970s oil crises, today we must start looking at water from a fresh economic perspective. We can no longer afford to consider water a virtually free resource of which we can use as much as we like in any way we want.
Instead, for all uses except the domestic demand of the poor, governments should price water to reflect its actual value. This means charging a fee for the water its
A. be reduced to the minimum
B. stimulate domestic demand
C. correspond to its real value
D. take into account the occurrences of droughts