当主语是第三人称单数时,谓语动词就用动词第三人称单数形式。 如:She often goes shopping on Sundays.她经常星期天去购物。
动词第三人称单数形式的构成规则:
a) 直接在动词词尾加s。如:help→helps, play→plays。
b) 以-s, -x, -ch, -sh, -o等结尾的动词,在词尾加-es。如:guess→guesses,
watch→watches, go→goes。
c) 以辅音字母加y结尾的动词,变y为 i再加-es。如:carry→carries, fly→flies。
若要把含有动词第三人称单数形式的句子改为否定句或疑问句,应用助动词does加动词原形来构成。其结构为:
否定句:主语 + do / does + not + 动词原形 + 其它
疑问句:Do / Does + 主语 +动词原形 + 其它?
答语:Yes, 主语+do / does. No, 主语+do / does not.
例如:Nick often plays with you. →(否定句)Nick doesn't often play with you. →(一般疑问句)Does Nick often play with you?
