apple
An apple a day keeps the doctor away.
意： 一日一苹果，不用看医生。每天吃个苹果身体健康。
the apple of
用：这个习语表示某人最喜爱的人或物。
o心肝儿，宝贝儿，宠儿：宠物
例. She had another son,who was the apple of her eye.
她还有个儿子，那儿子是她的心肝儿宝贝。
Oh, darling, don't say so, you're the apple of my eye!
啊，亲爱的，可别这么说，你可是我的心肝儿哟。
Hey, don't touch that car, it's the apple of my son's eye.
哏，别动那车，那可是我儿子的宝贝