2.用于世上独一无二的事物名词前

the universe, the moon, the Pacific Ocean

3.表示说话双方都了解的或上文提到过的人或事

Would you mind opening the door?

5.用于形容词和分词前表示一类人

the living, the wounded

6.表示“一家人”或“夫妇”

the Greens, the Smiths

7.用于序数词、形容词和副词的比较级、最高级前

He is the taller of the two children.

8.用于国家党派等以及江河湖海、山川群岛的名词前

the United States, the Communist Party of China

9.用于表示发明物的单数名词前

The compass was invented in China.

10.在逢十的复数数词之前，指世纪的某个年代

in the 1990’s

11.用于表示单位的名词前

I hired the car by the hour.

12.用于方位名词、身体部位名词前

in the east / He patted me on the shoulder.