英语中,第三人称单数主语(he, she, it或单数名词)的谓语动词变化与其他人称不同,包括一般现在时在动词后加-s,现在进行时在be动词后加-ing,一般过去时在动词后加-ed,过去进行时在be动词后加-ing,现在完成时用have/has + 过去分词,过去完成时用had + 过去分词。特殊情况包括以-s, -x, -z, -sh, -ch结尾的动词在后加-es,以及以辅音字母+y结尾的动词在y变为i后加-es。
- 一般现在时:在动词原形后加 -s,例如:he walks, she talks, it runs.
- 现在进行时:在be动词后加 -ing,例如:he is walking, she is talking, it is running.
- 一般过去时:在动词原形后加 -ed,例如:he walked, she talked, it ran.
- 过去进行时:在be动词后加 -ing,例如:he was walking, she was talking, it was running.
- 现在完成时:用have/has + 过去分词,例如:he has walked, she has talked, it has run.
- 过去完成时:用had + 过去分词,例如:he had walked, she had talked, it had run.
需要注意的是,有些第三人称单数主语的谓语动词变化不符合以上规则。例如:
- 以 -s, -x, -z, -sh, -ch 结尾的单词,在动词原形后加 -es,例如:he watches, she fixes, it buzzes.
- 以辅音字母 + y 结尾的单词,在y变为i后加 -es,例如:he tries, she carries, it flies.