英语的句子成分大体上有以下：

　　1.主语：TomiswatchingTVnow.Tom就是主语.

　　2.谓语：TheystudyEnglishhard.stud是谓语.y

　　3.宾语：Iplaybasketballeveryafternoon.play就是宾语.

　　4.定语：Maryboughtapen.pen是宾语.

　　5.状语：Heisreadingabookcarefullyintheroomnow.carefully方式状语,intheroom地点状语,now时间状语.

　　6.表语：Theyarestudents.They是主语,are是连系动词,students就是表语.

　　7.补语：

　　Thebosstoldtheworkerstobecareful.tobecareful是宾语theworkers的补语,叫宾语补足语,简称宾补.

　　Theworkersweremadetowork12hoursaday.towork12hoursaday是主语theworkers的补语,叫主语补足语,简称主补.