-Look, I can copy from anybody without my teacher('s) seeing.
Is that a good way to construct a sentence?Because I always see people use this style ''without + someone + Ving ''.
Is that grammatically OK?
You can use the possessive. In that context (plagiarism) I'd expect something like 'without my teacher finding out' (because I have an old-fashioned feeling that cheating students would use a form of grammar that teachers in my schooldays used to say was wrong .