Каждый пассажир должен сам проверять своё место в билете.

Each passenger must check their seat in the ticket themselves.

Breakdown of Каждый пассажир должен сам проверять своё место в билете.

• в: in
• билет: the ticket
• должен: must
• каждый: each

Questions & Answers about Каждый пассажир должен сам проверять своё место в билете.

Why is it должен, not должны, even though we’re talking about all passengers?

In Russian, каждый (each / every) is grammatically singular, even if logically it refers to many people. The verb and other agreeing words must therefore be singular too.

• Каждый пассажир должен… – Each passenger must… (singular: one passenger at a time)
• Все пассажиры должны… – All passengers must… (plural: all passengers together)

So you use должен (3rd person singular, masculine) because it agrees with каждый пассажир (singular, masculine), not with the idea of “all passengers.”

What exactly does сам mean here, and why is it needed?