Рецепт на очки не меняется, если только не меняется острота зрения.

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Breakdown of Рецепт на очки не меняется, если только не меняется острота зрения.

• меняться: to change
• если только не: unless
• рецепт на очки: the glasses prescription

Questions & Answers about Рецепт на очки не меняется, если только не меняется острота зрения.

Why is it рецепт на очки, not something like рецепт для очков?

In Russian, рецепт на что-то is the normal way to say a prescription for something, especially in medical and pharmacy-related language.

So:

• рецепт на очки = a prescription for glasses
• рецепт на лекарство = a prescription for medicine

Here на does not literally mean physical movement onto something. It is just the standard preposition used in this expression.

Also note that очки is in the accusative case after на, but because очки is an inanimate plural noun, its accusative form looks exactly like the nominative:

• nominative: очки
• accusative: очки

Why is очки plural? Can Russian not say it in the singular?

Russian normally uses очки only in the plural, just like English usually says glasses rather than a glass when talking about eyewear.

So:

• очки = glasses
• there is no normal everyday singular form meaning one pair of glasses

This kind of noun is called plural-only in practice for ordinary usage.

What exactly does рецепт mean here? Is it the same word as recipe?