Yesterday is history.Tomorrow is mistery.Only today is the present,that's why it was called gift.

你写的句子本身就错了,应该是：
Yesterday is a history.Tomorrow is a mystery.Only today is a gift,that's why it's called present.(出自功夫熊猫,乌龟大师的话）
你把gift和present的位置写错了,位置错了意思就不对了.
这句话的意思是：
昨天是历史,明天是未知,只有今天是一份礼物,这就是为什么我们称它为present（在英文中同时有“礼物”和“现在”的意思）.