Я подмела кухню веником, а мелкий мусор собрала совком.

In the past tense, Russian verbs agree with the gender and number of the subject.

Here the subject is я, and the verb forms tell us the speaker is female:

• я подмёл = I swept up (male speaker)

• я подмела = I swept up (female speaker)

• я собрал = I collected (male speaker)
• я собрала = I collected (female speaker)

So this sentence is being said by a woman or girl.

This is a question of aspect.

• подмела is from подмести — perfective
• подметала is from подметать — imperfective

The perfective form is used because the speaker is talking about a completed action: the kitchen was swept, and the trash was collected.

So:

• Я подметала кухню = I was sweeping / I used to sweep the kitchen / I swept the kitchen (focus on process)
• Я подмела кухню = I swept the kitchen up / I finished sweeping the kitchen (focus on result)

The same idea applies to собрала from собрать: it presents the action as completed.

Because кухню is the direct object of the verb подмести.

The sentence means that the speaker swept the kitchen as the thing affected by the action. In Russian, a direct object usually goes in the accusative case.

• кухня = nominative
• кухню = accusative

Compare:

• Я подмела кухню. = I swept the kitchen.
• Я была на кухне. = I was in the kitchen.

So:

• на кухне = location
• кухню = object of the action

They are in the instrumental because they express the tool or means used to do the action.

• веник = broom

• веником = with a broom

• совок = dustpan / scoop
• совком = with a dustpan

This is a very common use of the instrumental case in Russian.

Examples:

• писать ручкой = to write with a pen
• резать ножом = to cut with a knife
• подмести веником = to sweep with a broom

So веником and совком answer the question чем? — with what?

А often connects two clauses that are contrasted, compared, or set side by side. It can sometimes be translated as and, and sometimes as but, depending on the context.

Here, а links two related but distinct actions:

• first, the kitchen was swept with a broom
• then, the small trash was collected with a dustpan

It creates a slight contrast in method or stage:

• sweeping with a broom
• collecting with a dustpan

If you used и, it would sound more like simple addition:

• Я подмела кухню веником и собрала мелкий мусор совком.

That is also possible, but а gives a stronger sense of dividing the actions into two parts.

Russian often leaves out repeated words when they are already clear from context.

So:

• Я подмела кухню веником, а мелкий мусор собрала совком.

means the same as:

• Я подмела кухню веником, а я мелкий мусор собрала совком.

The second я is unnecessary because the subject is obviously still the same speaker.

Russian does this very naturally, especially in compound sentences.

Because мелкий мусор is the direct object and мусор is an inanimate masculine noun.

For inanimate masculine nouns in the singular, the accusative looks the same as the nominative:

• nominative: мелкий мусор
• accusative: мелкий мусор

That is why the adjective stays мелкий, not мелкого.

Compare with an animate noun:

• Я вижу маленького кота. = I see a small cat.

Here the accusative matches the genitive because кот is animate.

But with мусор:

• Я собрала мелкий мусор.

No change in form is needed.

Here мелкий means something like:

• small
• fine
• tiny
• little bits of

So мелкий мусор is not just small trash in a literal size sense. It often means small scattered bits of debris, the kind you gather with a dustpan after sweeping.

It is a very natural phrase in this context.

Yes. They describe two different actions:

• подмести = to sweep up
• собрать = to gather / collect

When cleaning a floor, Russian often separates these steps:

1. sweep the floor or room with a broom
2. gather the remaining small debris with a dustpan

So the sentence is very natural: first the sweeping, then the collecting.

The dictionary forms are:

• подмести = to sweep up
• собрать = to collect / gather

The past tense feminine forms are:

• подмела
• собрала

A learner may notice that подмела does not look very similar to подмести. That is normal: some Russian verbs change their stem in different forms.

For example:

• подмести
• я подмету
• он подмёл
• она подмела

So this is a verb you simply need to get used to as a pattern.

Yes. Russian word order is flexible, and different orders can change the emphasis.

The given sentence is natural and neutral enough:

• Я подмела кухню веником, а мелкий мусор собрала совком.

But you could also say:

• Я веником подмела кухню, а совком собрала мелкий мусор.
• Кухню я подмела веником, а мелкий мусор собрала совком.

These versions are still grammatical, but they shift the focus:

• веником / совком first = emphasis on the tools
• кухню first = emphasis on what was cleaned

Russian word order is often about information focus, not just grammar.