这项研究追踪了一组1995年出生的年轻人。

The research tracked a ___cohort of people born in 1995.

这项研究跟踪了1990年出生的同龄人群的健康状况。

The study followed the health of the 1990 birth ___cohort.

他和往常一样，和一群老伙计们去了酒吧。

He went to the bar with his usual ___cohort of old buddies.