1、含义不同，jack作名词时意思为千斤顶、起重器、插座、J牌，作动词意思为顶起、离开、停止、放弃、增加等；jacky意思为杜松子酒。2、发音不同，前者发音为“d？k”；后者发音为“？d？ki”。3、都可用作人名，一般译为杰克，但后者更亲切些。

例句：1、Jack is doing very well at school.

杰克在学校里学习成绩斐然。

2、After five years,he decided to jack it all in.

五年后，他就决定完全放弃了。

3、I'm jacking into the Internet now.

我正要接入互联网。

4、I turned to Jacky,my nostrils flaring in disgust

我转过身厌恶地看着杰基，鼻翼呼呼地翕动着。

5、However,Jacky Cheung really did very well.

应该说，张学友演得很好。