W tym warsztacie sprawdzają hamulce, silnik i światła.

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Breakdown of W tym warsztacie sprawdzają hamulce, silnik i światła.

• i: and
• ten: this
• światło: the light

Questions & Answers about W tym warsztacie sprawdzają hamulce, silnik i światła.

Why is it w tym warsztacie and not w ten warsztat?

Because after w meaning in/at for location, Polish normally uses the locative case.

• dictionary form: ten warsztat = this workshop / this garage
• locative after w: w tym warsztacie = in/at this workshop

So:

• tym is the locative form of ten
• warsztacie is the locative form of warsztat

Does warsztat here mean workshop or garage?

In this sentence, warsztat most naturally means an auto repair shop / garage. A very natural English translation would be At this garage or In this repair shop.

So W tym warsztacie... is more about the place where cars are serviced, not a school workshop or craft studio.

Who is doing the checking? Why is there no subject like oni?

The verb form sprawdzają already tells you it is 3rd person plural: they check.

Polish often leaves out subject pronouns when they are obvious from the verb ending. Here it means something like:

• they check
• the staff check
• people check

In this kind of sentence, it often has a general meaning: this is what they do there.