Когда голова и спина устали, я делаю паузу и просто хожу по комнате.

I

Breakdown of Когда голова и спина устали, я делаю паузу и просто хожу по комнате.

• комната: the room
• и: and
• когда: when

Questions & Answers about Когда голова и спина устали, я делаю паузу и просто хожу по комнате.

Why is устали in the past tense when the English translation is “are tired”?

In Russian, it’s very natural to use the past tense of устать (perfective: “to get tired / to have become tired”) in time clauses with когда to set up a condition:

• Когда голова и спина устали, я делаю паузу…
  Literally: When the head and back have (already) become tired, I take a break…

So Russian is focusing on the result of a completed process: at the moment when you decide to act, the “getting tired” has already happened. English usually uses the present state are tired, but Russian comfortably uses the past result устали here.

You could also say:

• Когда голова и спина устают, я делаю паузу…

That sounds a bit more like a general habit without emphasizing completion; устали adds a slight feeling of “once they’ve gotten tired.” Both are acceptable, but устали is very common and natural.

---

Why is устали plural if голова and спина are each singular?