2--Apples and eyes? It has to do with love, listen:
 
1--Jack is a great dad. He is so attached to his daughter he would do anything for her.
 
2--Wow, you are right about that. She sure is the "apple of his eye"!
 
1--"Apple of his eye" means a person, or thing, is precious, or loved deeply.
 
2--The center of one's eye, the pupil, is dark and round.
 
1--This phrase comes from long ago when people believed that the eye's pupil was solid and shaped like an apple.
 
2--And of course, the pupil was precious, because you can't see without it.
 
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注解：
 
1.Apple of One's Eye心肝宝贝 
2.attached依恋的
3.pupil瞳孔

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译文：

1--如果你听过美式英语，你也许知道这个短语：心肝宝贝
2--苹果和眼睛？这个短语和爱有关系，让我们听一听。
1--杰克真是个好爸爸，他非常爱他的女儿，愿意为她做任何事情。
2--喔，没错。她可是他的心肝宝贝。
1--"Apple of his eye"的意思是某人或某事很珍贵，深受别人喜爱。
2--眼睛的中心是瞳孔，瞳孔是暗色的、圆形的。
1--这个短语很久之前就有了，那时人们相信瞳孔是立体的、形状像苹果一样。
2--当然，瞳孔很珍贵，因为没有它，你什么也看不到。