Wikipedia:How to copyedit

This is a short but not exhaustive list of some of the more common errors you may find in articles.

Some style guides advise against grammatical constructions such as passive voice, split infinitives, restrictive which, beginning a sentence with a conjunction and ending clauses in a preposition. These are common in high-quality publications and should not be "fixed" without considering the consequences. Changing a passive to active may inappropriately change the topic of the paragraph, for example. Attempts to improve the language of a passage should be based on tone, clarity and consistency, rather than blind adherence to a regional or contested rule.

Correct spelling mistakes and typos. See for complete advice on how to do this well; the main points are:

According to Butcher's Copy-editing, "The good copyeditor is a rare creature: an intelligent reader and a tactful and sensitive critic; someone who cares enough about perfection of detail to spend time checking small points of consistency in someone else's work but has the good judgement not to waste time or antagonize the author by making unnecessary changes."

Articles in need of basic copyediting may be tagged with templates such as {{}} or {{}}. A list of such articles can be found in a few places. The easiest places to get started are:

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