> 形容词：通常形容人或事物的状态、性质、大小等，通常用在名词前，be动词之后。 beautiful-the beautiful girl ``` The girl is beautiful. ``` > The+形容词=复数名词，表示一类，后面的动词使用复数 old-the old young-the young ``` The old need more care than the young. ``` ``` She is a good student. This bike is expansive. The rich sometimes complain their empty life. 富人有时抱怨他们空虚的生活。 ```