Когда светофор станет зелёным, можно спокойно перейти улицу.

the street

Breakdown of Когда светофор станет зелёным, можно спокойно перейти улицу.

• когда: when
• можно: can
• светофор: the traffic light

Questions & Answers about Когда светофор станет зелёным, можно спокойно перейти улицу.

Why is зелёным in the instrumental case?

Because after the verb стать in the sense of to become / to turn, Russian normally uses the instrumental case for the resulting state.

So:

• стать зелёным = to become green / to turn green

Here:

• зелёный = green
• masculine singular instrumental = зелёным

This is very common in Russian:

• стать врачом = to become a doctor
• стать ясным = to become clear
• стать старше = to become older

So светофор станет зелёным literally means the traffic light will become green.

Why is станет used instead of будет?

Станет comes from стать, which means to become / to turn into. In this sentence, the important idea is the change from one color to another.

• Когда светофор станет зелёным = When the traffic light turns green
• Когда светофор будет зелёным = When the traffic light is green / will be green

Both can make sense, but станет is more natural when talking about the moment the light changes. It focuses on the transition, not just the state.

Why is перейти perfective, not переходить?