第九单元

　　1.常考单词：

　　classify approximate proportion appreciation acknowledge alter lengthen wealthy neglect expectation

　　2. 常考词组：

　　to approximate to　　 resistance to 　　 to cope with 　 attribute … to

　　3. 常考句子：

　　1） Nation classified as “aged” when they have 7percent of more of their people aged 65 or above. （para.1）

　　2） The nearer a society approximates to zero population growth，the older its population is likely to be - at least，for any future that concerns us now.

　　3） The older you are now，of course，the greater this proportion will be，and greater still if you are a woman.

　　4） If you are now in your thirties，you ought to be aware that you can expect to live nearly one third of the rest of your life after the age of 60.