2) The headmaster warned the children to keep off the garden . 校长警告孩子们勿踏花园。
　　2 . 在 have , make , let 等使役动词和 see , hear , watch , notice , feel 等
　　感官动词后面作宾补的不定式须省略不定符号 to。例如：
　　3) The teacher doesn\'t make his students do homework at school . 那位老师不让他的学生在学校里做家庭作业。
　　4) I heard someone knock at the door three times . 我听见有人敲了三次门。
　　注：上面第2类句式变为被动语态时，不定式符号 to 不能省略。如句4)变为被动语态应为：
　　Someone was heard to knock at the door three times . 只听见有人敲了三次门。
　　另外，help 后常用“宾语+(to)do”的形式(美国用法常省去 to)。例如：
　　He helped me (to) look after my child . 他帮我照看孩子。
　　二、后面用分词作宾语补足语的动词
　　1 . 在feel , find , get , have , hear , keep , see , send , watch 等动词后面可用现在分词作宾补。例如：
　　5) It was so cold that they kept the fire burning all night . 天很冷，他们让火燃了个通宵。
　　6) I had my car waiting outside . 我让汽车在外面等候。
　　2 . 在 find , get , have , leave , keep , see 等动词后可用过去分词作宾补。例如：
　　7) The speaker raised his voice but still couldn\'t make himself heard . 发言人提高嗓音但还是不能让别人听见他的话。
　　8) You should have left the door locked . 你该把门锁上。
　　三、分词、不定式作宾补在意义上的区别
　　现在分词作宾补，宾语在逻辑上是分词表示的动作的执行者；过去分词作宾补，宾语在逻辑上是分词表示的动作的承受者；省略了 to 的不定式作宾补只是表示一个事实，说明动作的全过程；带 to 的不定式作宾补往往表示不定式的动作发生在谓语动词的动作之后。试比较：
　　I heard a girl singing upstairs . (表示一个主动、进行的动作)
　　我听见一个女孩正在楼上唱歌。
　　I heard the song sung . (表示一个被动、完成的动作)
　　我听见有人唱过这首歌。
　　I heard a girl sing upstairs . (强调唱歌的事实)
　　我听到一个女孩在楼上唱歌。
　　I\'ll get someone to repair the recorder for you . (不定式的动作发生在谓语动词动作之后。)
　　我要叫人帮你修理录音机。
　　练习：用所给动词的正确形式填空。
　　1 . He had us all ____ (laugh) at his jokes .
　　2 . His jacket was in his bag that he had left ____ (hang) next to his seat .
　　3 . The girl had his arms ____ (hurt) in the accident .
　　4 . We have been warned ____ (be) careful of our health .
　　5 . He doesn\'t have to be made ____ (learn) . He always works hard .
　　6 . -Where is Li Hua ? Do you know ?
　　　　-I saw him ____ (enter) his bedroom just now .
　　Key :1 . laughing 2 . hanging 3 . hurt 4 . to be 5 . to learn 6 . enter
　
　　◆ 过去分词作表语
　　过去分词作表语具有下列特征：
　　（1）表达动作的完成性，这与被动语态没有关系，下列动词常用作表语：come , gp , arrive , fall , rise , set , finish , return 。如：
　　Autumn is come . = Autumn has come .
　　The sun is set . = The sun has set .
　　All the guests I invite are arrived . = All the guests I invite have arrived .
　　Father is just returned from his business trip . = Father has just returned from his business trip .
　　(2) 表示主语受外界的情况处于被动的状态。有时只表示主语所处的状态。如：
　　The playground lay / appeared / looked quite deserted (荒芜的) .