While these three words sound the same, they have slightly different meanings and usages. Preserve (verb form): to maintain or keep (保藏) I would like to preserve this tender memory for the rest of my life. Reserve (verb form): to keep something aside for a specific person/purpose (保留) I called the restaurant in advance to reserve a table for tonight. Conserve (verb): to use sparingly and cautiously (节省) We should not keep the air conditioner on all day, in order to conserve energy. Each verb can be used in many different ways - it might help if you had a specific example.

It may help a learner to pay attention to the etymology. Each of the words preserve, reserve, and conserve contains the same root, which comes from the Latin servare (keep, protect, save, maintain). Therefore reserve (re- indicates "back") becomes keep back or save back. Preserve (pre- indicates before) becomes save or maintain beforehand. Conserve (con- is an intensive prefix) becomes to keep intact or guard. As Steven mentioned, there are several different uses for these three words, but I really think it helps to remember the roots and prefixes.

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