It is mostly just traditional to use certain words in certain contexts. "Modify" is a broad word meaning "to change." It often refers to making changes to a physical object. "I bought a Dodge Viper and modified it by adding a twin turbo system." "I know young people with body modifications such as tattoos and piercings." But it can be applied to words or ideas: "If you want to get him to agree, I think you should modify your proposal a bit." "Revise" is often used when you are making your own changes to your own work, in response to criticism from others. "Your thesis is good, but I'd still like to see you revise section III, particularly your explanation of your statistical methodology." "Amend" is almost always used in connection with laws, rules, and parliamentary procedure. "I move to amend the proposal by striking the words 'subject to approval by the executive board.'"

Yes, all of these things mean "to change." But if you were specifically talking about a document, you would use revise or edit. While not always true, modify is to change something physical. You modify your car by adding extra speakers. Amend is used mostly in legal settings for changing documents and revise would be most used for more casual changes in papers etc..

If you had an office document or college paper you needed to change, you'd revise it, thus making some updated changes. If you had something like a church constitution with its bylaws, and you wanted to make a change, then you could amend it. Modify would probably not be the most popular word for a document change. I'd modify my F-350 Ford diesel truck by upgrading my turbo and chipping it. :) Merrit

Hi Nami, The way I see it, each one does mean change but the context of the change/degree of change varies for each. Amend - suggests that, however it was originally, it was wrong. To make something 'right/correct'. In a document, it may be bad grammar or spelling for example. 'Modify' - a change that is more wholesale. Bigger scale change. Making concerted effort to change the make up of something from its original form. Modify settings of a machine. Or code. Or a car is modified (speakers, body) as mentioned above. note there is not right or wrong here. Revise - re view (look again) something AND make a change based on new information or new opinion. (Note here review is an action where no change is applied). Hope that helps,