When using request as a noun, we often add the preposition for when we refer to what is being requested. (We can also add an infinitive after request, but that’s another story.]
- This is my third request for new staplers.
- They made a request for further aid. [Oxford Advanced American Dictionary]
- She filed/sent/submitted a formal request for more information. [Learner’s Dictionary]
When using request as a verb, we don’t need a preposition.
- I requested new staplers.
- She requests an audience with the pope.
- She requested permission to film at the White House. [Oxford Advanced American Dictionary]
- You can request a free copy of the leaflet.
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