Koliko grama sira kupujete?

Kupujete is the 2nd person plural present form of kupovati, the imperfective verb to buy.

In this sentence, it can mean either:

• are you buying
• do you buy

The exact English translation depends on context.

It can refer to either:

• you all / you plural
• you as a polite or formal singular

So the sentence could be addressed to several people, or to one person in a formal situation.

Serbian often leaves out subject pronouns when the verb ending already shows who the subject is.

Here, -te in kupujete already tells you it is you plural/formal you, so vi is not necessary.

You could say Koliko grama sira vi kupujete?, but that would usually sound more emphatic or contrastive, not neutral.

Because koliko normally requires a quantity form, and with countable nouns that is usually the genitive plural.

The noun gram becomes grama in the genitive plural:

• jedan gram
• dva grama
• pet grama
• koliko grama

So koliko grama means how many grams.

Because after a measure word like gram / grama, the thing being measured goes into the genitive.

So:

• gram sira = a gram of cheese
• deset grama sira = ten grams of cheese

Here, sira is the genitive form of sir.

It is genitive singular.

That is because sir here means cheese as a substance, not separate individual cheeses. In English, this is also treated as a mass noun in most contexts.

So:

• sir = nominative
• sira = genitive singular

Because kupujete comes from the imperfective verb kupovati, which is the normal choice for an ongoing or general action like buying.

Kupiti is the perfective partner, and its present forms usually do not mean a normal present action. They often point to a future or completed action instead.

So in a neutral question like this, kupujete is the natural form.

It can mean either one.

Serbian present tense often covers both:

• an action happening now
• a habitual or general action

In real life, context tells you which is meant. If someone is at a deli counter, the most natural meaning is How many grams of cheese are you buying?

No, Serbian word order is fairly flexible, but this version is the most neutral for asking about the quantity:

Koliko grama sira kupujete?

It starts with koliko grama sira because that is the main information being asked about.

Other orders are possible, but they may sound marked, emphatic, or like an echo question.

Yes. That means How much cheese are you buying?

This version asks about the amount without naming the unit.
Koliko grama sira kupujete? is more specific because it asks for the quantity in grams.

You would usually say:

Koliko grama sira kupuješ?

Here, kupuješ is the 2nd person singular informal form.

So:

• kupuješ = you singular informal
• kupujete = you all or you formal

Because Serbian does not have articles like English a / an / the.

Whether the meaning is definite or indefinite is usually understood from context.

So sira can mean:

• cheese
• the cheese
• some cheese

depending on the situation.