I am a non-native English speaker, and one of the things that often trip me is the usage of do vs does(and don't vs doesn't) in speech and writing.
What are the grammar rules around the usage of these verbs?
There was a related question which was closed because it was too localized.
Update: Maybe I wasn't clear in my description. I sometimes misuse the words do and does, and would like to know the general rules around when to use these words?