Οι εθελοντές προστατεύουν τα ζώα και τα πουλιά του δάσους όταν κινδυνεύουν.

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Breakdown of Οι εθελοντές προστατεύουν τα ζώα και τα πουλιά του δάσους όταν κινδυνεύουν.

• όταν: when
• το ζώο: the animal
• ο εθελοντής: the volunteer

Questions & Answers about Οι εθελοντές προστατεύουν τα ζώα και τα πουλιά του δάσους όταν κινδυνεύουν.

What does Οι mean here, and why do we use the article with εθελοντές?

Οι is the definite article in the nominative plural (for masculine or mixed gender), and it means “the”.

In Greek, you almost always use the article with plural nouns referring to a whole class of people:

• Οι εθελοντές προστατεύουν…
  = Volunteers protect… / The volunteers protect…

Even if in English you might say just “Volunteers protect animals…” with no article, Greek prefers Οι εθελοντές.

If you drop the article (Εθελοντές προστατεύουν…), it sounds either:

• like you’re announcing the arrival of some volunteers (“Volunteers are protecting… right now”), or
• more like “Some volunteers…” rather than a general statement about volunteers as a group.

What is the form and gender of εθελοντές, and what is the singular form?

εθελοντές is:

• masculine,
• nominative plural,
• from the noun εθελοντής = volunteer.

Basic forms:

• Singular: ο εθελοντής – the volunteer
• Plural: οι εθελοντές – the volunteers

Even if the group includes women, Greek grammar uses the masculine plural by default for mixed groups of people.

What tense and person is προστατεύουν, and what is the basic verb?