Acid rain destroys forests and has a serious impact on ecosystems.

The ecosystem of this lake is very fragile.

The destruction caused by this earthquake was immense.

His actions exerted a great influence on our plans.

We like to walk in the forest on weekends.

The acidity of this lemon is very strong.

His opinion had a big influence on my decision.

That news greatly influenced his opinion.

This problem is very serious.

Do you understand the seriousness of this problem?