我们一起在大学学习了4年，我们度过的很开心，用英语怎么说？

We have been enjoying our lives during these four years when we study together in our university.

We studied together for four years in college/university, we all/both had a wonderful time.

We've studied together in the university for 4 years,
and we had a good time.

We've studied together in the college for 4 years and spent a happy time.

We've studied together in the university for 4 years,
and we had a great time.

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