Stand-up and Sit up

Stand-up adjective - Following the accepted rules of moral conduct.

Sit up and stand-up are semantically related. In some cases you can use "Sit up" instead a verb phrase "Stand-up".

Sit up verb - Change to an upright sitting position.

Stand-up and sit up are semantically related. Sometimes you can replace phrase "Stand-up" with "Sit up", this terms are similar.