Yeğenim salıncakta gülünce ben de gülmeden edemiyorum.

Yeğen means niece or nephew. Turkish does not distinguish gender here, so yeğenim can mean either my niece or my nephew.

The ending -im is the 1st person singular possessive suffix, meaning my.

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

So the speaker is talking about their own niece or nephew.

Salıncak means swing.

The ending -ta is the locative suffix, meaning in, on, or at, depending on context.

• salıncak = swing
• salıncakta = on the swing / in the swing / at the swing

In natural English, on the swing is probably the best translation here.

The suffix appears as -ta rather than -da because the final consonant of salıncak is voiceless, so Turkish uses the voiceless form of the suffix.

This is because of consonant harmony.

The locative suffix has four common forms:

• -da
• -de
• -ta
• -te

Which one appears depends partly on the final sound of the noun.

Since salıncak ends in a voiceless consonant sound, the suffix becomes -ta rather than -da:

• evde = at home
• okulda = at school
• parkta = in the park
• salıncakta = on the swing

So this is a normal sound pattern in Turkish.

Gülünce comes from the verb gülmek, meaning to laugh or to smile.

Here, the ending -ince / -ınca / -ünce / -unca means something like:

• when
• once
• as soon as

So:

• gülmek = to laugh
• gülünce = when he/she laughs, when my niece/nephew laughs

Because of vowel harmony, the suffix appears here as -ünce.

In this sentence, gülünce introduces a time clause: When my niece/nephew laughs on the swing...

The subject is yeğenim.

Turkish often does not repeat the subject once it is already clear. So in:

Yeğenim salıncakta gülünce...

the meaning is: When my niece/nephew laughs on the swing...

Even though there is no separate word for he/she inside gülünce, the subject is understood from yeğenim.

Here, de means too, also, or as well.

So:

• ben = I
• ben de = I too / me too / I also

In this sentence, it gives the idea that the niece/nephew laughs, and then the speaker laughs too.

Important: this de is written separately, because it is a particle meaning also/too.

Compare:

• ben de = I too
• evde = at home

Those are completely different things, even though they may sound similar.

Yes, Turkish often drops subject pronouns when they are already clear from the verb ending.

So in many contexts, edemiyorum already tells us the subject is I, because -um marks first person singular.

However, ben is included here for emphasis or contrast, especially with de:

• ben de = I too

So it sounds natural because the speaker is reacting to someone else’s laughter: My niece/nephew laughs, and I laugh too.

This is one of the most important parts of the sentence.

The pattern -meden / -madan edememek is an idiomatic Turkish structure meaning:

• cannot help doing
• can't stop oneself from doing
• can't help but do

So:

• gülmeden edemiyorum = I can’t help laughing

Even though gülmeden by itself means without laughing, the whole expression does not mean a simple literal without laughing, I can't do in normal English. It is a set pattern.

A useful way to think of it is:

• gülmeden edemiyorum
  = I cannot manage not to laugh
  = I can’t help laughing

So you should learn -meden edememek as a chunk.

It breaks down like this:

• gül- = laugh
• -meden = without doing
• ede-...-miyorum = I cannot do / I am unable to do

Together:

• gülmeden edemiyorum
  literally: I cannot do without laughing
• natural meaning: I can’t help laughing

So the grammar is built from smaller pieces, but the whole phrase functions as an idiom.

Because the sentence describes two different actions by two different subjects:

1. yeğenim ... gülünce
   = when my niece/nephew laughs
2. ben de gülmeden edemiyorum
   = I can’t help laughing too

So the same verb appears twice because:

• first, the niece/nephew laughs
• then, the speaker laughs as a reaction

This repetition is completely natural in Turkish.

Edemiyorum is in the present continuous form.

It means something like:

• I am unable to
• I can’t
• I’m not able to

In this sentence, it expresses a general present habit/reaction: whenever the niece/nephew laughs on the swing, the speaker also ends up laughing.

So although the form is present continuous, in English the best translation is usually simple present: I can’t help laughing.

Turkish very often puts the background clause or time clause first, and the main clause later.

So the structure is:

• When my niece/nephew laughs on the swing,
• I can’t help laughing too.

This order is very natural in Turkish.

Turkish frequently places information like:

• time
• condition
• cause
• context

before the main action.

It most often means something like:

• when
• once
• as soon as

The exact English wording depends on context.

In this sentence, when is the safest and most natural choice:

• When my niece/nephew laughs on the swing, I can’t help laughing too.

But the feeling can also suggest an immediate reaction: As soon as my niece/nephew laughs on the swing, I start laughing too.

Yes. The most idiomatic part is:

gülmeden edemiyorum

That pattern is extremely common in Turkish and is worth memorizing. You can use it with many verbs:

• bakmadan edemiyorum = I can’t help looking
• sormadan edemedim = I couldn’t help asking
• gülmeden edemiyorum = I can’t help laughing

So even if you understand each individual word, the natural meaning comes from recognizing the whole pattern.