As far as I understand, you complain about students' insuffiencent knowledge of English. Using translator software may be helpful (see my reply to https://www.researchgate.net/post/Are_you_taking_help_from_AI_to_write_a_manuscript), but when using it one has to understand the result and be able to check whether the translated text is what one wanted to say. However, I did not understand the connection to plagiarism. Could you please explain this?

• Thanks for your reply. Translator Machine is very good for our Non-native language writing, It is very convenient to solve some less noticed spelling errors and misuse.Sometimes I also use it to check what I've written.
• However, A contact letter is not a professional document for a PhD application, Just for expression and general communication.It can be seen from the contact letter that the applicant has the ability of daily use and communication in English. If he can only use translation software for daily communication and cannot provide the result of English proficiency test, it is worrying that the recruited doctor cannot communicate with his colleagues and supervisors normally. And the fact that he uses translation software to hide his true language skills is a bit dishonest, I think.