What is a synonym for did?

There isn't one perfect synonym for "did" because it depends on the context. Here are some options depending on the situation:

For past actions:

* Performed - "He performed the task flawlessly."

* Completed - "She completed her homework."

* Accomplished - "We accomplished our goal."

* Executed - "They executed the plan perfectly."

* Finished - "I finished reading the book."

* Made - "He made a mistake."

For questions:

* Have/Has - "Have you seen the movie?" (present perfect)

* Did (used in a question) - "Did you go to the store?"

* Have/Has done - "Have you done your homework?" (present perfect)

Other:

* Worked - "I worked on the project all day." (implied action)

Remember to choose the best synonym based on the specific sentence and its meaning.