l am a slow walker . but l never walk backwards.

我走的很慢，但是我从来不会后退。

life consists of not only sunshine . but also hard times.

生活中不仅有阳光，还有艰难困苦的时候。

【四级词汇】
alter v. 改变，改动，变更
……………………………………
Remember what should be remembered, and forget what should be forgotten.Alter what is changeable, and accept what is unchangeable.
记住该记住的，忘记该忘记的。改变能改变的，接受不能改变的。