Simple and general:
* The environment is important to protect.
* We should all do our part to improve the environment.
Specific examples:
* The company is committed to reducing its impact on the environment.
* The environment in the rainforest is incredibly diverse.
* The children learned about different environments around the world.
* The environment of the office was very casual.
Figurative:
* The environment of the meeting was very tense.
* He felt out of his environment at the fancy party.
You can use "environment" to describe the physical surroundings, the conditions in a specific place, or even the social or emotional atmosphere of a situation.