Yeğenimle bahçede top oynadık.

Yeğenimle = yeğen-im-le

• yeğen = nephew / niece
• -im = my
• -le = with

So yeğenimle literally means with my nephew/niece.

Turkish often stacks endings onto one word like this, instead of using separate words the way English does.

It can mean either.

Turkish yeğen is gender-neutral, so it does not tell you whether the person is male or female. The context usually makes that clear, or it may simply not matter.

So yeğenimle can mean:

• with my nephew
• with my niece

Both are possible.

• yeğenimle
• yeğenim ile

They both mean with my nephew/niece.

The shorter attached form -le / -la is extremely common in everyday Turkish. It is basically the same word as ile attached to the noun.

So:

• annemle = with my mother
• arkadaşımla = with my friend
• yeğenimle = with my nephew/niece

Because English my is expressed in Turkish with a possessive ending.

• yeğen = nephew / niece
• yeğenim = my nephew / my niece
• yeğenimle = with my nephew / niece

If you said yeğenle, that would mean something more like with the nephew/niece or with a nephew/niece, depending on context — not specifically my.

Bahçede means in the garden or at the garden.

It breaks down like this:

• bahçe = garden
• -de = location ending, meaning in / at / on

So:

• evde = at home
• okulda = at school
• bahçede = in the garden

This is called the locative ending.

This is due to vowel harmony and consonant harmony.

For the locative ending, Turkish chooses among:

• -da
• -de
• -ta
• -te

In bahçede:

• the last vowel in bahçe is e, so the ending must use e: -de / -te
• the word ends in a vowel sound, so the voiced form -de is used

So we get bahçede.

Literally, it is something like we played ball.

Breakdown:

• top = ball
• oynadık = we played

In Turkish, top oynamak is a normal expression meaning to play ball or sometimes more generally to play a ball game, depending on context.

So the whole sentence means that we played ball in the garden with my nephew/niece.

Oynadık comes from the verb oynamak = to play.

Breakdown:

• oyna- = verb stem, play
• -dı- = past tense, did / played
• -k = we

So oynadık means we played.

Because the subject is built into the verb, Turkish does not need a separate word for we.

Because Turkish verbs already show the subject.

Oynadık already means we played, so adding biz (we) is usually unnecessary.

You could say:

• Biz yeğenimle bahçede top oynadık.

But that usually adds emphasis, like we played, or helps contrast with someone else.

The shorter sentence without biz is more neutral and very natural.

Because top oynamak is treated like a general activity: play ball.

The bare noun top works here in a broad, non-specific way, similar to English play ball.

If you used topu, that would mark the ball as a specific object, and it would sound different. In normal Turkish, top oynamak is the standard expression for this activity.

No, Turkish word order is fairly flexible, although some orders sound more neutral than others.

The sentence:

• Yeğenimle bahçede top oynadık.

is perfectly natural.

You could also hear:

• Bahçede yeğenimle top oynadık.
• Topu bahçede yeğenimle oynadık.
  This changes the nuance because topu is specific.

In Turkish, the word right before the verb often gets a bit of focus. But the most important thing is that the endings show the relationships clearly.

No. Oynadık specifically means we played.

Here are the relevant forms:

• oynadım = I played
• oynadın = you played
• oynadı = he/she/it played
• oynadık = we played
• oynadınız = you all / you formal played
• oynadılar = they played

So in this sentence, the subject must be we.

Yes. Turkish -de is broader than any one English preposition.

Depending on context, bahçede may be translated as:

• in the garden
• at the garden
• sometimes even out in the garden

English chooses the most natural preposition for the situation, but Turkish simply uses the locative ending -de.

Not necessarily.

Top oynamak can mean:

• to play with a ball
• to play ball
• to play a ball game
• in some contexts, even to play football/soccer informally

The exact meaning depends on context. In this sentence, the natural interpretation is simply that we played ball in the garden.