The syntactic characteristics of AI feedback and human feedback in academic writing are examined in this paper.We analyzed 200 feedback samples  in terms of sentence construction, use of clauses, cohesion, and politeness.The results indicate that human feedback tends to consist of complex, compound–complex sentences and the use of hedging, along with modal verbs with more linguistic diversity.AI feedback instead prefers shorter, concise structures that emphasize understanding and minimize the number of errors.