They came in flocks to see the procession.

他们成群结队来看游行队伍。

《牛津词典》

The migratory birds gather in flocks along the coast and gradually drift southward.

候鸟沿着海岸成群聚集，并逐渐南移；

youdao

No cases have been linked to the consumption of properly cooked poultry meat or eggs, even in households where disease was known to be present in flocks.

没有发现病例与食用经适当烹煮的禽肉或蛋类有关，即便是已知在禽群中出现该病的家庭中也是如此。

youdao

One would be characteristic of semi-nomadic pastoralists: the sacrifice of the first lamb born in the spring to the deity in order to procure favor and continued blessing on the flocks for the spring.

一种是具有半游牧人的特色：,他们把春天里的第一只羊羔献给神,为了获得神的偏爱,来年春天继续赐福。

耶鲁公开课 - 旧约导论课程节选

Everything else is covered by snow, so pigeons are attacking in flocks.

BBC: How are farmers coping with the snow?

Black pied crows perch in their dead branches and then suddenly take off in flocks to surf the swirling breezes around the dunes.

CNN: Romancing the dune in Namibia

According to the US Geological Survey, the American Buff-Bellied Pipit is 5.5in (14cm) in length and is usually found in flocks in ploughed fields, shores and tundra.

BBC: American Buff-Bellied Pipit