Katsumi (2024) stated that GPT-4o and GPT-4o mini had difficulty with analyzing the meaning of sentences with adjuncts and it is because there are adjectives which are intersective, subsective and both intersective and subsective. However, whether GPT-5.1 has no difficulty analyzing these sentences correctly is unknown. In this paper, we will look at this topic by giving a list of adjectives and observing whether GPT-5.1 can successfully divide them into intersective and subsective group. Also, we will let GPT-5.1 analyze three sentences used in Katsumi (2024) and see if it understands the difference between intersective and subsective modifiers.