Learn Hardcore Russian: Моя подруга тоже копит деньги, чтобы купить билет на концерт. - My friend female is also saving money to buy a ticket to a concert.

подруга does not automatically mean “girlfriend” in the romantic sense. It is mainly “(female) friend”.
Context or extra words (like девушка, моя девушка) are used for “girlfriend” in the romantic sense.

What tense/aspect is копит, and how would you translate it?

Копит is:

3rd person singular
Present tense
Imperfective aspect of the verb копить (“to save up, to accumulate [money]”).

Russian doesn’t have a special continuous form like “is saving”. The simple present often corresponds to English “is doing”:

Она копит деньги. = “She saves money.” / “She is saving money.”

Here it clearly means “is saving (over a period of time)”, a repeated or ongoing action.

Is копить деньги a common phrase? Could I say something else?

Yes, копить деньги is very common and idiomatic: it means “to save up money”, often over time for a specific goal.

Alternatives (with slightly different nuances):

экономить деньги – to economize, to save money by spending less.
собирать деньги – to gather/collect money (could be donations, contributions, etc.).
откладывать деньги – to put money aside regularly.
скопить деньги – perfective: to have managed to save up a certain amount.

In this sentence, копит деньги nicely fits the idea of gradually saving up for a ticket.

Why is деньги in the plural? In English, “money” is uncountable.

In Russian, деньги is grammatically plural-only:

You never say a singular form like деньга in normal modern speech (it exists but is rare and stylistic).
So деньги can mean “money” in general.

Here:

копит деньги = “is saving money”.

Grammatically, it’s accusative plural, because деньги is the direct object of копит, but accusative and nominative plural forms are the same: деньги.

Why is чтобы used here, and what does it do grammatically?

Чтобы introduces a purpose clause (“in order to …”).

The pattern is:

[Main clause], чтобы + infinitive / finite verb

In this sentence:

Моя подруга тоже копит деньги, чтобы купить билет на концерт.
= “My friend is also saving money in order to buy a ticket to the concert.”

Key points:

With the same subject in both parts (she is saving, she will buy), it’s very natural to use чтобы + infinitive (купить).
Чтобы is written as one word and is usually pronounced like [штобЫ].

Why is it купить, not покупать, after чтобы?

Купить and покупать are two aspects of the same verb:

покупать – imperfective (“to be buying,” repeated, process, general).
купить – perfective (“to buy once and complete the action”).

After чтобы, when you talk about a single, intended result in the future, Russian normally uses the perfective:

чтобы купить билет = “in order to buy (and have bought) a ticket.”

If you said чтобы покупать билет, it would sound like the goal is to buy tickets regularly or repeatedly, which is not the idea here.

What case is билет in, and why doesn’t its form change?

Билет is in the accusative singular, because it is the direct object of купить:

купить что? – билет

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

Nominative: билет (a ticket)
Accusative: билет (buy a ticket)

So even though the form doesn’t change, the function in the sentence is accusative.

Why is it на концерт and not в концерт?

Both на and в can mean “to” with motion, but they are used in different contexts.

With events (concert, lecture, meeting, show, performance), Russian normally uses на:

на концерт – to (a) concert
на лекцию – to a lecture
на вечеринку – to a party

So:

купить билет на концерт = “to buy a ticket to the concert.”

В концерт is incorrect in this meaning. You might see в концерте with prepositional case meaning “in a concert” in some special contexts (e.g. “he took part in a concert”), but not for “to a concert” as a destination.

What does тоже do here, and where can it go in the sentence?

Тоже means “also / too / as well.”

In this sentence:

Моя подруга тоже копит деньги…
implies: someone else (probably I or another person) is saving money, and my friend is also saving.

Typical placement:

After the subject, before the verb:
- Моя подруга тоже копит деньги. – The friend is also saving.
If you move тоже, the nuance can change:
- И моя подруга копит деньги. – “And my friend is saving money (too).”
- Моя подруга копит тоже деньги. – sounds odd; could emphasize that what she’s saving is also money (weird focus).

So the most natural place is exactly where it is: after the subject, before the verb.

Why is there a comma before чтобы?

Russian uses a comma to separate the main clause from a subordinate clause introduced by чтобы when it expresses purpose.

Structure here:

Main clause: Моя подруга тоже копит деньги
Subordinate purpose clause: чтобы купить билет на концерт

Russian punctuation rule: a subordinate clause is usually separated by a comma from the main clause, so the comma is mandatory here.

How do you pronounce and stress the main words in this sentence?

Approximate stresses (capital letters show the stressed syllable):

Моя́ подру́га то́же ко́пит де́ньги, что́бы купи́ть биле́т на концéрт.

Rough pronunciation tips:

моя́ – [ma-YA]
подру́га – [pa-DRU-ga]
то́же – [TO-zhe]
ко́пит – [KO-pit]
де́ньги – [DYEN’-gi] (soft д
- е gives something like “dye”)
что́бы – usually sounds close to [SHTO-by]
купи́ть – [ku-PEET’] (final ть is soft)
биле́т – [bee-LYET]
концéрт – [kan-TSERT]

Correct stress is very important in Russian; putting it on the wrong syllable can make words hard to understand.