Question

请教几个英语语法中的问题。

Domineering parents may keep kids under their thumb to try to protectthe kids from the perils of peer pressure. But this approach may backfire andactually make kids more susceptible to going with the crowd. So finds a studyin the journal Child Development.
这之中的最后一句So finds是一种什么用法？
Then the researchers followed up with the study participants when theywere 18 and again when they reached 21 of particular interest were interactions with a peer or romantic partner.
这句话interest后面的were是不是多加了？

Answer 1

finds肯定是错误的，要嘛你打错，要嘛是印刷错误。
when引导的从句里，主语是they，谓语是reached，不可能再来个were。