Bušilicom sam napravila rupu iznad police.

Bušilicom is the instrumental singular of bušilica (drill).

Serbian often uses the instrumental case to show the tool or means used to do something. So:

• bušilica = a drill
• bušilicom = with a drill / using a drill

Because bušilica is a feminine noun ending in -a, its instrumental singular here becomes -om.

Not usually in this kind of sentence.

When Serbian expresses the instrument used to do something, it often uses the instrumental case by itself, without sa:

• Pisao sam olovkom. = I wrote with a pencil
• Sečem nožem. = I cut with a knife
• Bušilicom sam napravila rupu. = I made a hole with a drill

Using sa is possible in some contexts, but for a tool, the plain instrumental is the most natural choice.

This is the perfect tense, one of the most common past tenses in Serbian.

It is formed with:

• the present tense of biti (to be)
• plus the past participle

So here:

• sam = I am (auxiliary form used in the perfect)
• napravila = past participle of napraviti

Together, sam napravila means I made / I have made.

Because the speaker is female.

In Serbian, the past participle agrees with the speaker’s gender in the singular:

• napravio sam = I made (male speaker)
• napravila sam = I made (female speaker)

So this sentence was said by a woman.

Serbian word order is fairly flexible, but sam is a clitic, and clitics usually go in the second position of the clause.

So if the sentence begins with Bušilicom, then sam naturally comes right after it:

• Bušilicom sam napravila rupu iznad police.

If you start with Napravila, then sam follows that:

• Napravila sam rupu bušilicom iznad police.

Both are possible, but they may sound a little different in emphasis. Starting with Bušilicom puts more focus on the tool used.

Because rupu is the accusative singular of rupa.

Here, rupa is the direct object of the verb napraviti (to make), so it must be in the accusative:

• rupa = hole (nominative)
• rupu = hole (accusative)

This is very common with feminine nouns ending in -a:

• knjiga → knjigu
• soba → sobu
• rupa → rupu

Because the preposition iznad (above) normally takes the genitive case.

So:

• polica = shelf (nominative)
• police = shelf / of the shelf (genitive singular)

That is why Serbian says:

• iznad police = above the shelf

Not:

• iznad policu — wrong case here
• iznad polica — that would usually be genitive plural, meaning above the shelves

Because Serbian has no articles.

English distinguishes:

• a hole
• the hole
• a shelf
• the shelf

Serbian does not normally mark that with separate words. The listener understands it from context.

So rupu can mean:

• a hole
• the hole

And iznad police can mean:

• above a shelf
• above the shelf

In real conversation, context tells you which is meant.

Because Serbian often omits subject pronouns when they are not needed.

The form sam already shows first person singular (I), so ja is unnecessary.

So:

• Bušilicom sam napravila rupu iznad police.
• Ja sam bušilicom napravila rupu iznad police.

Both are grammatical, but the version without ja is more neutral and natural unless you want to emphasize I.

This is a question of aspect, which is very important in Serbian.

• napraviti = perfective → to make, to finish making, to produce a result
• praviti = imperfective → to be making, to make in a general or ongoing sense

In this sentence, the speaker is talking about a completed result: the hole was made. So napravila is the natural choice.

Compare:

• Bušilicom sam napravila rupu. = I made a hole with a drill.
• Pravila sam rupu... = I was making a hole... / I used to make a hole...

The second one sounds unfinished or context-dependent.

Yes, often it can. Serbian allows more word-order freedom than English.

For example:

• Bušilicom sam napravila rupu iznad police.
• Napravila sam rupu bušilicom iznad police.
• Rupu sam napravila bušilicom iznad police.

The basic meaning stays similar, but the focus changes:

• Bušilicom... emphasizes the tool
• Rupu... emphasizes the object
• iznad police at the end is a natural place for the location

Even though the order can move, case endings like bušilicom, rupu, and police still show each word’s role.

In this sentence, the most natural interpretation is that the hole is above the shelf.

So the structure is understood as:

• I made a hole above the shelf
• using a drill

Because bušilicom is in the instrumental and clearly marks the instrument, it is less likely to be understood as the thing located above the shelf.

If you wanted to avoid any possible ambiguity, Serbian could also rephrase the sentence, but as it stands, the usual reading is clear.