I had studied calculus before I got into college.

我在上大学以前，已经学过微积分成。

youdao

I had studied calculus before I got into college.

我在上大学以前，已经学过微积分。

youdao

I had studied calculus before I got into college.

我在上大学以前，已经学过微积分。

youdao