Pár měřidel je v domě.

Here pár means a couple of or a few. So Pár měřidel means a couple of measuring instruments / a few gauges.

A useful thing to know is that pár can also mean a pair or a couple in other contexts, but in this sentence it simply means a small number of things.

Because pár is followed by the genitive plural in standard Czech.

The dictionary form is měřidlo = measuring instrument / gauge / measuring device.
Its plural nominative is měřidla, but after pár you use the genitive plural, which is měřidel.

So:

• měřidlo = one measuring instrument
• měřidla = measuring instruments
• pár měřidel = a couple of measuring instruments

This is a very common pattern in Czech with quantity expressions.

Because the subject is treated grammatically as the quantity expression pár měřidel, and with pár Czech often uses a singular verb in standard usage.

So:

• Pár měřidel je v domě.

This may feel strange to an English speaker, because English would normally say A couple of gauges are in the house. But in Czech, the singular verb is normal here.

V domě is in the locative singular.

The preposition v usually means in and, when it expresses location, it requires the locative case.

The noun is:

• dům = house

After v, it becomes:

• v domě = in the house

So the pattern is:

• dům → v domě

Because after v when you mean location, Czech uses the locative, not the dative or genitive.

For dům, the locative singular is domě.

So:

• v domě = in the house

By contrast, domu is a different case form and would not be correct here for this meaning.

Yes, Pár měřidel je v domě is grammatically correct and understandable.

However, Czech often prefers location-first or existential-style word order in sentences like this, so a very natural alternative is:

• V domě je pár měřidel.

This often sounds a bit more natural if you are simply stating that some items are located somewhere.

Very roughly:

• Pár měřidel je v domě. = focuses a bit more on the measuring instruments
• V domě je pár měřidel. = focuses a bit more on what is in the house

Both are fine.

Měřidlo is a somewhat technical word. It means a measuring instrument, gauge, or measuring device, depending on context.

Possible translations include:

• gauge
• meter
• measuring instrument
• measuring device

The best English choice depends on what kind of object is meant.

No, not in this sentence.

When pár means a couple as in two people together, it behaves differently and the context would make that clear.

Here, because it is followed by měřidel in the genitive plural, it clearly means a couple of / a few measuring instruments.

No. After pár, standard Czech uses the genitive plural, so měřidla would be wrong here.

Correct:

• Pár měřidel je v domě.

Not correct in standard Czech:

• Pár měřidla je v domě.

So this is an important pattern to memorize:

• pár + genitive plural

Not always.

Originally, pár is closely connected with the idea of a pair / two, but in everyday Czech it often means a couple of or a few, just like in English.

So in many contexts, pár měřidel may suggest a small number, often around two, but not necessarily exactly two.

The letter ě is important in Czech. It usually signals that the preceding consonant is pronounced differently, often with a y-like sound added or with softening.

In these words:

• měřidel
• domě

the ě affects pronunciation, but it is not pronounced like a separate full syllable ye in a simple English way.

A learner should mainly notice that:

• mě is not the same as me
• dě, tě, ně, mě are very common Czech combinations

Also, ř in měřidel is a famously difficult Czech sound for English speakers. It is a special Czech consonant, not just a normal r.

Czech does not have articles like a and the, so the sentence itself does not explicitly mark that difference.

Pár měřidel je v domě can mean something like:

• A couple of measuring instruments are in the house
• There are a couple of measuring instruments in the house

The exact nuance depends on context, not on an article.