I did it to please my parents.

我这么做是要让父母高兴。

I did it by mistake.

我误做了这事。

I didn't do it for reward; I did it for love.

我做这件事不是为了报酬；我做这件事是出于爱。

After you begin to talk to someone or smile at someone for the first time, remember to say "I did it! " to yourself.

当你第一次和别人说话或微笑时，记得对自己说：“我做到了！”

Some of my classmates did this for an easy way to meet their intermediate course requirement, but I did it to get the kind of depth in those topics I was going for.

我的一些同学这样做是为了更轻松地达到他们中级课程的要求，但我这样做是为了更深层次地研究那些我感兴趣的主题。

I did it because he told me to.

是他吩咐我才做的。

You think I did it deliberately, but I assure you (that) I did not.

你认为这是我故意干的，不过我向你保证不是的。

I did it so badly that some of my classmates laughed at me.

我做得很糟糕，以至于我的一些同学都嘲笑我。

I got to know that if I had done my best for the first time I did it, I wouldn't have so many differences.

我知道，如果我第一次做到最好，我就不会和别人差这么多。

"I did it," he said, reflecting.

“是我干的。”他沉思着说。

If I did it, just think what would happen!

如果我做了，想想会发生什么事！

The work took 3 hours and I did it all myself.

这项工作花了3个小时，是我全由自己做的。

I did it only because I felt it to be my duty.

我做此事仅仅是因为我觉得它是我的责任。

I did it because they asked me to do it!

我做这事是因为他们请我做啊！

I did it, and so can you.

我可以做到这些，你也可以。

I did it for his benefit.

我做这个是为了帮助他。

I don't even know why I did it.

我甚至到现在都不明白为什么我会那样。

I did it when I was in college.

我在大学时玩过。

I did it just for kicks.

我只是为了好玩才做那件事的。

If I did it, you can do it, too.

如果我战胜了疾病，你们也能战胜的。

I don't know how I did it.

我不知道我是怎么做到的。

I don't know why I did it.

我不知道我为什么去了。

You think, I did it.

你会想，我做到了。

Would you like to know how I did it?

你想知道我是如何做到的吗？

Now she thinks I did it.

现在她以为是我干的。

Continues fell but eventually, I did it.

继续，最后我做到了。

I didn't do it very fast, but I did it.

我跑得并不快，但是我确实完成了。