英語的句子成分大體上有以下：
1.主語：Tom is watching TV now.Tom就是主語.
2.謂語：They study English hard.stud是謂語.y
3.賓語：I play basketball every afternoon.play就是賓語.
4.定語：Mary bought a pen.pen是賓語.
5.狀語：He is reading a book carefully in the room now.carefully方式狀語,in the room地點狀語,now時間狀語.
6.表語：They are students.They 是主語,are是連系動詞,students就是表語.
7.補語：
The boss told the workers to be careful.to be careful是賓語the workers的補語,叫賓語補足語,簡稱賓補.
The workers were made to work 12 hours a day.to work 12 hours a day是主語the workers 的補語,叫主語補足語,簡稱主補.