中文意思不同、用法不同。give up on的中文含义为“对...绝望”“对...不抱希望”，表示不再信任、相信;give up的中文含义为“放弃”、“投降”、“戒除”，表示将某物让给、交给或献给他人。
一、give up on的意思及用法
give up on意为对…绝望;对…不抱希望。例句有：
1、He urged them not to give up on peace efforts
他力劝他们不要放弃对和平的努力。
2、They have led some birds to give up on migration.
它们已导致一些鸟类放弃迁徙。
3、They'll have to give up completely on certain of their studies.
他们将不得不彻底放弃某些研究。
4、I've been trying to give up smoking for getting on for two years now
到现在，我设法戒烟已快两年了。
5、Every time I'm about to give up on this business.
每次我打算放弃工作的时候。
6、Good teachers will never give up on their students.
好老师绝对不会放弃他们的学生。
二、give up的意思及用法
give up意为放弃;戒除;认输;辞去(工作);让出;自首;投案。例句有：
1、Coastguards had given up all hope of finding the two pers alive.
海岸警卫队对两位潜水员生还已完全不抱希望。
2、After a fruitless morning sitting at his desk he had given up.
他在书桌前徒劳地坐了一上午之后便放弃了。
3、She gave up her job to join her husband's campaign...
她辞去工作，加入到丈夫的宣传活动中。
4、Georgia refuses to give up any territory...
格鲁吉亚拒绝出让任何领土。
5、He suffered a serious injury that obliged him to give up work.
他受伤严重，不得已只好放弃工作。
