It can be seen that certain groups are more at risk than others.

看得出，有的组风险大，有的组风险小。

《牛津词典》

If individuals on the edge of a group are more vigilant because they are at greater risk of being captured, then individuals on average would have to be more vigilant in smaller groups.

如果处于群体边缘的个体由于被捕获的风险更大而变得更加警惕，那么个体通常在较小的群体中就必须更加警惕。

youdao

As with all diseases, certain groups will be more at risk than others.

所有的疾病都是如此，一些人比另一些人更容易受到威胁。

《牛津词典》

And they are advising against travel by children, pregnant women and other groups at highest risk.

VOA: special.2009.11.24

You can see that when you get out to the highest groups here, the highest weights, the relative risk is up at two and a half or three, so that would be a 200% increase in risk for cardiovascular death or two to three times the risk of death.

当我们看图上相对风险最高的这组,也就是体重最大的这组,这组的相对风险大约是2.5倍到3倍,即心血管疾病致死的风险增加了200%,或者说增加了2到3倍

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

She says children are at risk of sexual violence, killing and maiming, and forced recruitment into armed groups.

VOA: standard.2010.02.04

At risk groups include the over-65s, pregnant women, people with weakened immune systems and other health conditions.

BBC: Flu cases rise over Christmas break

Currently it is estimated that only around half of those at risk groups are taking up the vaccine.

BBC: Liberal Democrats debate

He said early evidence had suggested up-take was not higher than previous years and there should have been enough doses for all the at risk groups.

BBC: NEWS | Health | Q&A: Flu jabs