its是所有格,意思是它的
只是一个单词,表示所有格.
its ear is black,
它的耳朵是黑色的.
it's是两个单词,it is的缩写,意思是它是,
it's a cat,它是只猫.
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反身代词:
单数:
I -> myself
you ->yourself
she -> herself
he -> himself
it -> itself
one -> oneself
复数:
you -> yourselves
we -> ourselves
they -> themselves