difference between swarm, flock and herd

[anand]

English Grammar Tests, Elementary Level

ESL/EFL Test #89 "Common Quantity Nouns", question 6

A swarm of ......... gathered around the swamp.

(a) sheep
(b) birds
(c) insects
(d) cows

English Grammar Tests, Elementary Level

ESL/EFL Test #89 "Common Quantity Nouns", answer 6

A swarm of insects gathered around the swamp.

Correct answer: (c) insects
_________________________

What is the difference between swarm, flock and herd?
As all of them has same dictionary meaning.

anand

[Conchita]

A herd is a group of large animals, for example domestic animals like cattle or pigs.

A flock is a group of similar animals together, especially sheep, goats and birds.

A swarm is a large group of insects, etc., flying about together.