问题

the average age of the population increases, there are more and more old people to care for.

A:Unless
B:Until
C:As
D:While;

正确答案是：

同类题型

.Only in this way ______ get rid of the bad habit-smoking.

How soon will Harry be back —–He said he would come back _____ twodays.

What were you up to when yourparents came in— I ____ for a while and ____ some reading

I wanted to have a word with her, but she______ me and went away.[ ]

Why do people never cut up the _______________ on their birthdays-Because they are a symbol of long life.