1.表示上文已經(jīng)提到的人或物,或特指某人或某物.
例如：I'm very interested in the film.
Give me the book.
Who is the girl you just said hello to?
2.表示世界上獨一無二的東西.
例如：the air ,the earth ,the moon,the sun,the sky
3.對兩個人或物比較時起特定作用的比較級之前.
例如：He is the taller of the two children in his family.
4.用在形容詞最高級、序數(shù)詞和last,next,only,same,right,wrong之前
例如：the largest room,the second story,the same school,the only one,the wrong way