sit, settle, rest
Someone who has a sedentary habit, job, or lifestyle spends a lot of time sitting down without moving or exercising often.
Someone who is sedulous works hard and performs tasks very carefully and thoroughly, not stopping their work until it is completely accomplished.
If you are sedate, you are calm, unhurried, and unlikely to be disturbed by anything.
When something supersedes another thing, it takes the place of or succeeds it.
Differentiated vocabulary for your students is just a click away.