我历史考试没及格——不过，另一方面，我也没有为它做太多学习。

I failed my history test - but ___then ___again, I didn't do much studying for it.

如今人们寿命更长确实有一些优势，但另一方面，它也导致了很多问题。

The fact that people live longer nowadays does have some advantages, but ___then ___again it also causes a lot of problems.

她非常有才华，但另一方面，她已经接受过多年的训练。

She is very talented, but ___then ___again, she has had years of training.