(1)保持(留，有)(keep possession of;continue to have)[T+n](尤fml)：～one's post as minister of finance/the governorship of Mississippi/the secretary-generalship 保留(继续担任)财政部长的职位/密西西比州的州长/秘书长的职务;～heat/one's balance 保持热量/平衡;～one's characteristics/all one's interest in life/some independence/a certain reserve and dignity 保持自己的特点/自己生活中所有的兴趣/一定程度的独立/某种沉默与尊严;～control of the situation 仍控制着局势;You must～your tickets. 必须保留票据。The flowers～their scent. 这些花仍有香味。〖同〗preserve，keep possession of;

(2)记住(remember sth without difficulty)[T+n](尤fml)：～knowledge/information 记住知识/信息;～the numbers/the dates/the facts 记住那些数字/日期/事实;～the tune but not the words of the song 记得那首歌的曲调，但记不住歌词;Be sure to take notes since you can't possibly～everything he says. 既然你不可能记住他所说的每件事，那么一定要记笔记。～a clear impression/memory of the accident 对那一事故印象很深/记得很清楚;〖同〗remember，recollect;

(3)挡(存、拦)住(prevent sth falling，running，etc out)[T+n](尤fml)：build a wall/a dyke to～the water from the river/the floods 修一座屏障/一座堤坝以挡住那条河的水/洪水;soil/plants that～(s)water/moisture 能保存水份/湿气的土壤/植物;The cracked jar can't～water. 那个有裂纹的坛子存不住水。a～ing wall 土埝;挡土墙;〖同〗hold，keep;

(4)聘请(律师)(engage the service of a lawyer by the payment of a fee)[T+n](尤fml)：～a lawyer 聘请一位律师;a～ing fee 律师费;

→ re′tainer n 律师费;侍从;(为保留所租用的房子而付的)定金;re′tention n 保持(留);记忆力;挡(留)住;re′tentive adj 有保持力的;(记忆力)强的;

【辨异】retain与keep和reserve的区别见KEEP。