This is the 345th most frequent Russian word.
мероприятия
"Мероприятия" in English means "events" or "activities."
In this sentence, 'мероприятия' refers to 'events' or organized activities for a specific purpose, such as extracurricular activities for students.
Мы организуем различные мероприятия для школьников.
We organize various events for students.
Here 'мероприятия' is used to mean 'measures' or 'actions' taken to achieve a goal, in this case, ecological improvement.
Мероприятия по улучшению экологии включают посадку деревьев.
Activities for improving ecology include planting trees.
In this instance, 'мероприятия' again refers to 'events' or scheduled activities that were planned but were canceled due to external circumstances.