行为动词的变化。
肯定句：主语+动词原形(+其它)。
否定句：主语+ don't( doesn't ) +动词原形(+其它)。
如：I like bread. I don't like bread.
当主语为第三人称单数时，要用doesn't构成否定句。
如：He ofter plays football.
He doesn't often play football.
一般疑问句：Do( Does ) +主语+动词原形+其它。(句首加助动词do, does)
如：I often play football.
- Do you often play football?
- Yes, I do. / No, I don't.
当主语为第三人称单数时，要用does构成一般疑问句。
如：She goes to school by bike.
- Does she go to school by bike?
- Yes, she does. / No, she doesn't.
特殊疑问句：疑问词+一般疑问句。
如：She goes to school by bike.
Does she go to school by bike?
How does she go to school?
动词+s的变化规则
1.一般情况下，直接加-s，如：cook-cooks, milk-milks
2.以s. x. sh. ch. o结尾，加-es，如：guess-guesses, wash-washes, watch-watches, go-goes
3.以“辅音字母+y”结尾，变y为i, 再加-es，如：study-studies
