愚公，NewVoice,小薇，Newton等同学（若有落下的同学不好意思啊，比较仓促）都用对了。语法功底深厚。
原文是对过去时的虚拟：要是我在年轻时养成了这种习惯，就可以避免时间上惊人的浪费。
愚公： If I had cultivated this habit while I were young, I would have not waisted a staggering amount of time.
小薇：If I had had this good habit when I was young, I would have avoided huge waste of time.
NewVoice： If I had acquired such habit in my youth, I would have avoided wasting a great amount of my time.
Newton：It would have avoided an astonishing waste of time if I had been accustomed to such habit when I was young.
