inattentive
🇺🇸
/ˌɪnəˈtentɪv/
🇬🇧
/ˌɪnəˈtentɪv/
Not focusing or paying attention to something or someone.
He was so inattentive in class that he missed the important lecture.
他上课时太不专心了,以至于错过了重要的讲座。