点击收听音频讲解：

Day 7

You cannot improve your past, but you can improve your future. Once time is wasted, life is wasted.

你不能改变你的过去，但你可以让你的未来变得更美好。一旦时间浪费了，生命就浪费了。

Key words:

improve v. 改善；step on=boost

future n. 未来; in the future/near

waste v. 浪费；错过waste the opportunity/lose; let the opportunity slip(溜走）