Formal:
* The farmer set traps to eliminate the vermin that were destroying his crops.
* The city council declared a war on vermin to improve public health.
* Scientists are studying the impact of vermin on the local ecosystem.
Informal:
* That old house is full of vermin - I saw a rat running across the floor!
* The cat chased the vermin out of the garden.
* We need to get rid of the vermin before they start chewing on the furniture.
Figurative:
* He considered the gossiping neighbors to be nothing but vermin.
* The politician denounced the opposition party as a pack of vermin.
Note: "Vermin" is often used to describe small animals considered pests, but it can also be used figuratively to describe people or groups seen as undesirable or harmful.