那时我才意识到分享的意义。

I have a brother. He is younger than me. When our parents have bought us presents, I will be the first to take presents, or if there is something to eat, I will make the choice before my brother. My mother educates me that I should share things with my brother. Until then I realize the meaning of sharing. 
我有一个弟弟。每当父母给我们买礼物时，我都会第一时间去拿礼物，或者如果有吃的东西，我也会抢在弟弟前面先选择。妈妈教育我应该和弟弟分享东西。直到那时我才意识到分享的意义。