当主语是第三人称单数时，动词形式有以下几种变化：
规则 一般动词在词尾加-s,在清辅音后读/s/，在 浊辅音或元音后读/z/，在t后读/ts/，在d 后读/ds/。 动词原形 第三人称单数形式 help like swim listen know play get find 以字母s, x, sh, ch结尾的动词加-es, 读/iz/。如果动teach 词原形词尾已有e，则加s。以o结 尾的动词也加-es，读/z/。 以辅音字母加y结尾的动词，先边y为i， 再加-es，读/z/。 一．写出下列动词的三单形式：
sit-- guess-- die-- go-- rush-- reach-- touch-- brush-- fly-- copy-- say-- run-- do-- fix-- live-- cry-- enjoy-- have-- wish-- play-- Tie-- teach-- buy-- study-- drink-- go-- stay-- make-- look-- carry-- come-- watch-- plant-- fly -- do-- 二、用括号内动词的适当形式填空。 1. He often ________(have) dinner at home. 2. Daniel and Tommy _______(be) in Class One. 3. We _______(not watch) TV on Monday.
study studies go helps /helps/ likes /laiks/ swims /wimz/ listens /’lisənz/ knows /nəʊz/ plays /pleiz/ gets /gets/ finds /faindz/ teaches goes 4. Nick _______(not go) to the zoo on Sunday. 5. ______ they ________(like) the World Cup? 6. What _______they often _______(do) on Saturdays? 7. _______ your parents _______(read) newspapers every day? 8. The girl _______(teach) us English on Sundays.
9. She and I ________(take) a walk together every evening. 10. There ________(be) some water in the bottle. 11. Mike _______(like) cooking. 12. They _______(have) the same hobby.
13. My aunt _______(look) after her baby carefully. 14. You always _______(do) your homework well. 15. I _______(be) ill. I’m staying in bed.
16. She _______(go) to school from Monday to Friday. 17. Liu Tao _______(do) not like PE.
18. The child often _______(watch) TV in the evening. 19. Su Hai and Su Yang _______(have) eight lessons this term. 20. －What day _______(be) it today? － It’s Saturday