If we posted an essay we had written and asked a teacher to read and evaluate it, would we be able to delete the post after a teacher had read it so as to aviod someone using the essay for plagiarism, or is a question posted on this site permanently?

We can delete it.

If you posted an essay on a website or platform and asked a teacher to read and evaluate it, the ability to delete the post will depend on the specific website or platform's policies and features. In general, most websites allow users to delete their own posts, but some platforms might have different rules in place.

To determine if you can delete the post, you should check the specific website's terms of service or user guidelines. Look for information regarding post deletion and see if it is possible. If you cannot find this information, you can contact the website's support team for clarification.

It's worth noting that even if you delete the post, there is no guarantee that someone hasn't copied or saved your essay before you removed it. So, it's important to be cautious when sharing your work online and consider the potential risks of plagiarism or unauthorized use.

If you want to protect your work from being plagiarized, it might be advisable to only share it with trusted individuals, such as your teacher directly through email or a secured file sharing service.