“preoccupied”是形容词，意为“全神贯注的；心事重重的；被占用的”。其用法较为灵活，可作表语或定语，用于描述人或事物的状态。
全神贯注的：指某人将全部注意力集中在某件事情上，对外界的其他事物可能不太关注。例如，“He was so preoccupied with his work that he didn't hear me calling him.（他全神贯注于工作，都没听到我叫他。）” 这里“preoccupied with his work”就形象地描绘出他专注于工作的状态。
心事重重的：形容人内心有忧虑、烦恼等，导致注意力无法集中到其他事情上。比如，“She seemed preoccupied all day, probably because of the upcoming exam.（她一整天都看起来心事重重，可能是因为即将到来的考试。）” 说明她因为考试的事情而内心担忧。
被占用的：可用来表示某个空间、时间等已经被其他事物所占据，无法再用于其他用途。不过这种用法相对较少见，例如，“The conference room is preoccupied for the next two hours.（会议室接下来两小时已被占用。）”
作表语：通常放在系动词（如be, seem, appear等）之后，用来描述主语的状态。前面提到的“He was so preoccupied with his work...” 和 “She seemed preoccupied all day...” 中，“preoccupied”都作表语，分别描述了“he”和“she”的状态。
作定语：放在名词之前，修饰该名词，说明名词的特征或属性。例如，“The preoccupied look on his face told me that something was wrong.（他脸上心事重重的表情告诉我出了问题。）” 这里“preoccupied”修饰“look”，表明这种表情的特征是心事重重的。