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。

youdao

I didn't do it very well, but, if anything, he did it worse than I did.

我干得不太好，但其实他干得比我还糟。

《牛津词典》

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。

《牛津词典》

Deep in my heart I hated him, but I never said or did anything that showed him how I really felt.

VOA: special.2009.02.07

I'm a little short but I was doing OK. But I did do some research when I saw this book last year.

虽然款项很少，但是我还做得不错,我去年看这本书的时候，做了些调查。

普林斯顿公开课 - 人性课程节选

I guess, I, I think the reason I did is because about the time to do it is college, I think.

我想，我认为我这么做，是因为大学该是时候这么做了。

留学的优点是？ - SpeakingMax英语口语达人

"I don't think I disrespected any of the players - if I did I apologise, " said Lescott.

BBC: Lescott unhappy with Moyes claims

When I built my first company in the 90s, I did everything smart until I did everything stupid.

FORBES: What Does It Feel Like To Lose A Lot Of Money Quickly?

"I think that I spoke for a lot of Americans when I said what I did, " he said.

WSJ: Former Rep. Weiner's Record Includes Many Causes But Few Bills