Number/Determiner + 群 + Noun
群 (qún) is a measure word used to count groups or crowds of people or animals. It is placed between a number or determiner and the noun it modifies. For example, 这群年轻人 means "this group of young people."
一群小鸟从树上飞了起来。
yī qún xiǎo niǎo cóng shù shàng fēi le qǐlái.
A flock of small birds flew up from the tree.
这群年轻人每周末都去爬山。
zhè qún niánqīngrén měi zhōumò dōu qù páshān.
This group of young people goes hiking every weekend.
草地上有一群羊在安静地吃草。
cǎodì shàng yǒu yī qún yáng zài ānjìng de chī cǎo.
There is a flock of sheep quietly grazing on the grass.