من دیروز در پارک بازی نکردم، چون خسته بودم.

A natural breakdown is:

• من = I
• دیروز = yesterday
• در پارک = in the park
• بازی نکردم = did not play
• چون = because
• خسته بودم = I was tired

So the structure is basically:

• I + yesterday + in the park + did not play + because + tired was

That word order is normal in Persian, especially because Persian often puts the main verb near the end of the clause.

Yes. Persian often drops subject pronouns when the verb already makes the subject clear.

In this sentence:

• نکردم already shows I did not do
• بودم already shows I was

So من دیروز در پارک بازی نکردم، چون خسته بودم and دیروز در پارک بازی نکردم، چون خسته بودم are both fine.

Including من can add emphasis, contrast, or clarity.

This is the negative past form of the compound verb بازی کردن, which means to play.

Breakdown:

• بازی = play/game
• کردم = I did
• نکردم = I did not do

So:

• بازی کردم = I played
• بازی نکردم = I did not play

This is very common in Persian: many actions are expressed with a noun plus کردن.

Because Persian often uses compound verbs. Instead of one simple verb, it combines:

• a noun or adjective
• with a light verb such as کردن, شدن, دادن, زدن, etc.

So بازی کردن literally looks like to do play/game, but it simply means to play.

This pattern is extremely common in Persian, so getting used to it is very important.

In Persian, the negative prefix نـ is added directly to the verb.

So:

• کردم = I did
• نکردم = I did not do

Since بازی کردن is a compound verb, the negative goes on the verbal part, not on بازی:

• بازی نکردم = I did not play

Not:

• نبازی کردم

That would be incorrect.

Because in the past tense, Persian normally uses a form of بودن to mean was/were.

So:

• خسته هستم = I am tired
• خسته بودم = I was tired

Here:

• خسته = tired
• بودم = I was

So خسته بودم literally means tired was-I, or more naturally, I was tired.

بودم is the first-person singular past form of بودن, meaning to be.

It means:

• I was

Some useful related forms:

• بودم = I was
• بودی = you were
• بود = he/she/it was
• بودیم = we were
• بودید = you were
• بودند = they were

So in خسته بودم, the بودم tells you that the speaker is talking about themself in the past.

Yes, Persian word order is flexible, especially for adverbs like دیروز.

This sentence uses:

• من دیروز در پارک بازی نکردم

That is very natural. But you could also hear:

• دیروز در پارک بازی نکردم
• من در پارک دیروز بازی نکردم

The most natural choices usually put time expressions such as دیروز fairly early in the sentence.

So the original sentence sounds normal and clear.

Yes. Both are possible.

• در پارک = in the park
• تو پارک = in the park

Difference:

• در sounds more formal or written
• تو sounds more conversational and is very common in speech

So the original sentence is correct and slightly more standard/written in tone. In everyday speech, many people would say:

• دیروز تو پارک بازی نکردم، چون خسته بودم

چون means because.

It introduces the reason:

• چون خسته بودم = because I was tired

So the sentence has:

• main clause: من دیروز در پارک بازی نکردم
• reason clause: چون خسته بودم

This is very similar to English because I was tired.

Yes. Persian allows that too.

You can say:

• چون خسته بودم، دیروز در پارک بازی نکردم.

That means the same thing:

• Because I was tired, I did not play in the park yesterday.

The original version is probably the most straightforward, but both are correct.

Not always. In Persian writing, punctuation can be a bit flexible.

So all of these may appear:

• من دیروز در پارک بازی نکردم، چون خسته بودم.
• من دیروز در پارک بازی نکردم چون خسته بودم.

The comma helps readability, especially in longer sentences, but its absence would not make the sentence wrong.

It is mostly neutral to standard.

Reasons:

• در پارک sounds a bit more standard than conversational تو پارک
• the grammar is completely normal and natural

In very casual spoken Persian, someone might say:

• دیروز تو پارک بازی نکردم چون خسته بودم

That sounds more conversational, but the original sentence is still perfectly natural.

A very natural spoken version would often be:

• دیروز تو پارک بازی نکردم چون خسته بودم.

Two common conversational changes are:

• dropping من
• using تو instead of در

So the original sentence is correct, but everyday speech often becomes a little simpler.

Yes. Persian usually places the finite verb near the end of the clause.

So in:

• من دیروز در پارک بازی نکردم

the verb element نکردم comes at the end.

And in:

• چون خسته بودم

the verb بودم also comes at the end.

This is one of the biggest differences from English, where the verb usually comes much earlier.

A helpful transliteration is:

• man diruz dar park bazi nakardam, chon khaste budam

A rough pronunciation guide:

• من = man
• دیروز = dee-rooz
• در = dar
• پارک = paark
• بازی = baa-zee
• نکردم = na-kar-dam
• چون = choon
• خسته = khas-te
• بودم = boo-dam

The خ sound in خسته is the throaty sound also heard in words like German Bach or Scottish loch.

Persian does not normally use a direct equivalent of English the in the same way.

So پارک can mean:

• park
• the park

The context usually makes it clear.

If needed, Persian can show specificity in other ways, but very often no separate word is used for the.

So در پارک naturally means in the park here.