Sentence examples for do this from inspiring English sources

"do this" is correct and usable in written English.
It can be used as a command or instruction to someone, telling them to perform a specific action. Example: "Please do this assignment by tomorrow." (instruction to complete an assignment) "I'm not sure how to fix this, can you show me what to do?" (asking for someone to demonstrate a solution) "Do this carefully, it's fragile." (warning to handle something delicately).