第三人称后面接的动词形式就是第三人称单数形式 举例

下列人称都是第三人称单数：
she your sisiter(你姐姐) my mother(我妈妈) his aunt(他姑姑) Mary 等
he my father(我爸爸) your brother(你哥哥) her uncle （她叔叔） Tom 等
it your name(你的名字) my telephone number （我的电话号码） a dog a book this that
当句子的主语是第三人称单数时,在一般现在时态中,谓语动词会出现第三人称单数形式.
例如：Your brother watches TV every day.
My father likes bananas.
A dog has four legs.(狗有四条腿.)
Does Mary have a computer?
Tom doesn't have a TV.

I like to eat oranges.
He likes to eat bananas.
like为原形,likes为单三形式

主语是第三人称的情况有两种：单数或复数。而主语是单数第三人称的时候，后面的动词形式用单三形式。
例如：He teaches us English.
The woman likes shopping.