Old English dyde, past tense of do (v.). The only remainder in Germanic of the old linguistic pattern of forming a past tense by reduplication of the stem of the present tense. Far back in Germanic the equivalent of did was used as a suffix to make the past tenses of other verbs, hence the English -ed suffix (Old English -de).
1. He did not like to be caught out on details.
2. Well, at any rate, let me thank you for all you did.
3. The blame for the Charleston fiasco did not lie with him.
4. Brian counted to twenty and lifted his binoculars. Elena did the same.
5. She had met both sons and did not care for either.