inattentive
🇺🇸
/ˌɪnəˈtentɪv/
🇬🇧
/ˌɪnəˈtentɪv/
Not focusing or paying attention to something or someone.
He was so inattentive in class that he missed the important lecture.
그는 수업에 너무 부주의해서 중요한 강의를 놓쳤다.