when he 刷题, he always

lost points on the grammer section. At the end, in his ACT and SAT, he missed questions on grammer. So I am pretty sure he has problems with grammer. However, since his final scores are really high, he just does not want to hear a single word from me regarding how to further improve his grammer. I tell him he is going to learn the lesson in a bad way in college. He said he is ok with it. What can I say now? Just hope he learns the lesson sooner.