Când termin, voi arunca gunoiul.

Because after când (when), Romanian very often uses the present tense to talk about a future event.

So:

• Când termin = when I finish
• not literally when I am finishing

This works a lot like English:

• When I finish, I’ll take out the trash.

The future meaning is understood from the whole sentence, especially because the main clause is in the future: voi arunca.

Voi arunca is a standard Romanian future form.

It is built with:

• voi = future auxiliary for I
• arunca = infinitive/base form of to throw

So:

• voi arunca = I will throw / I will take out

This pattern works like:

• voi merge = I will go
• voi face = I will do
• voi termina = I will finish

In everyday speech, Romanians also often use o să for the future:

• O să arunc gunoiul. = I’m going to / I will take out the trash.

Romanian often leaves out subject pronouns because the verb ending already shows who is doing the action.

Here:

• termin = I finish
• voi arunca = I will throw

So eu (I) is not necessary.

You could say:

• Când termin, eu voi arunca gunoiul.

But that sounds more emphatic, as if you want to stress I specifically.

Gunoi means trash / garbage.

Gunoiul means the trash / the garbage.

The ending -ul is the Romanian definite article, which is attached to the end of the noun instead of being a separate word like English the.

So:

• gunoi = trash
• gunoiul = the trash

This is very common in Romanian:

• băiat = boy
• băiatul = the boy

Yes, literally a arunca gunoiul means to throw away the trash.

In real usage, it can match English take out the trash, depending on context. Romanian may also use:

• a duce gunoiul = to take the trash out / to carry the trash out
• a scoate gunoiul = to take the trash out

So voi arunca gunoiul is natural, but it focuses more on disposing of the trash rather than just physically carrying it outside.

Because Când termin is a subordinate clause placed before the main clause.

Romanian normally uses a comma here:

• Când termin, voi arunca gunoiul.

This is similar to English:

• When I finish, I’ll take out the trash.

If the order is reversed, the comma is usually omitted:

• Voi arunca gunoiul când termin.

Both versions are correct.

Yes. A very common alternative is:

• Voi arunca gunoiul când termin.

Both mean the same thing.

The difference is mostly about focus:

• Când termin, voi arunca gunoiul.
  This emphasizes the time condition first: When I’m done...
• Voi arunca gunoiul când termin.
  This starts with the main action: I’ll take out the trash...

Când is pronounced approximately /kɨnd/.

The tricky part is â, which represents a vowel that does not exist naturally in standard English. It is a close central vowel, something like a tight, central uh/ih sound.

A rough guide:

• c before â sounds like k
• â is a central vowel, not like English a
• nd sounds as expected

So când is roughly like k-uhnd, but with a more central, tighter vowel than normal English uh.

Termin comes from the verb a termina, meaning to finish.

Here it is conjugated in the 1st person singular present:

• eu termin = I finish
• tu termini = you finish
• el/ea termină = he/she finishes

So in Când termin, the full idea is:

• When I finish

You may encounter forms like that, but Când termin, voi arunca gunoiul is the more natural and usual phrasing.

With time clauses introduced by când, Romanian commonly uses the present tense even when the meaning is future.

So for a learner, the best model is:

• Când termin, voi arunca gunoiul.

That is the standard, idiomatic choice.