我的用英文怎么表达？?

Those were the best years of my life.

那些年是我一生最幸福的时光。

It was a chance meeting that would change my life.

那次偶然的会面改变了我的`一生。

It was the best day of my life.

这是我一生中最美好的一天。

In essence, your situation isn't so different from mine.

从本质上讲，你我的情况并非相差很远。

The engine is used for pumping water out of the mine.

这台发动机是用来从矿井中抽水的。