Arkadaşım da bugün gelmiyor.

It is:

• arkadaş = friend
• -ım = my

So arkadaşım means my friend.

Turkish often shows possession by adding an ending directly to the noun, instead of using a separate word like my.

This is because of vowel harmony.

The possessive ending for my can appear in different forms, such as:

• -ım
• -im
• -um
• -üm

The word arkadaş has the vowel a, which is a back vowel, so the correct form is -ım.

That is why you get arkadaşım.

Here da means too / also / as well.

So it adds the idea that my friend is included along with someone else already mentioned.

In English, in a negative sentence, this is often translated as either:

• My friend isn’t coming today either.

But in Turkish, the same word da/de is used in both positive and negative contexts:

• positive: too / also
• negative: often translated as either

Because this da is a separate particle, not a normal suffix.

So you write:

• Arkadaşım da

not:

• Arkadaşımda

This is a very common point for learners, because there is also a different -da/-de ending that means in / at / on and that one is written attached.

So:

• arkadaşım da = my friend too / as well
• arkadaşımda = at my friend / in my friend depending on context, though that second one would be unusual

You can tell by both meaning and spelling.

1. Meaning
   In this sentence, da adds too / also, which makes sense with the whole sentence.

2. Spelling
   The additive particle da/de is written separately.
   The locative suffix -da/-de is written attached to the word.

So:

• Arkadaşım da bugün gelmiyor. = My friend isn’t coming today either.
• Arkadaşımda... would mean something like at my friend’s place or in my friend, depending on context.

Yes, literally gelmiyor is the negative present continuous form:

• gel- = come
• -mi- = negative
• -yor = present continuous
• third-person singular has no extra ending here

So gelmiyor literally means is not coming.

But in Turkish, the present continuous is also very commonly used for planned or expected near-future actions, especially when there is a time word like bugün.

So bugün gelmiyor can naturally mean:

• isn’t coming today
• is not coming today
• sometimes effectively won’t be coming today

depending on context.

Because Turkish often drops subject pronouns when they are clear from context.

In English, you usually need to say:

• He isn’t coming
• She isn’t coming

But in Turkish, the verb form and context often make the subject clear enough, so o is often omitted.

Here, arkadaşım already tells you who the subject is: my friend.

So there is no need to add o.

This is a very natural Turkish word order.

A rough pattern is:

• subject
• other information such as time
• verb at the end

So here:

• Arkadaşım da = my friend too
• bugün = today
• gelmiyor = isn’t coming

Turkish word order is somewhat flexible, but the verb often comes last in neutral statements.

You could move parts around for emphasis, but this version sounds natural and standard.

Yes, Turkish allows some flexibility.

For example, these can all be possible depending on emphasis:

• Arkadaşım da bugün gelmiyor.
• Bugün arkadaşım da gelmiyor.

The basic meaning stays similar, but the focus changes slightly.

• Starting with bugün emphasizes today
• Starting with arkadaşım da emphasizes my friend too

The version you were given is a normal, natural sentence.

Because Turkish does not switch to a special word like English often does.

English usually says:

• My friend is coming too.
• My friend isn’t coming either.

Turkish uses the same additive particle da/de in both cases:

• positive: da/de = too / also
• negative: da/de = often translated as either

So in this sentence, although da literally feels like too/also, the natural English translation is often either because the sentence is negative.

It breaks down like this:

• gel- = come
• -mi- = not
• -yor = ongoing/present continuous

So:

• geliyor = is coming
• gelmiyor = is not coming

This is one of the most useful verb patterns in Turkish.

You will see the same structure with many verbs:

• yapıyor = is doing
• yapmıyor = is not doing
• gidiyor = is going
• gitmiyor = is not going

A few sounds may feel unfamiliar to English speakers:

• ş is pronounced like sh
• ı is a vowel that does not exist in standard English; it is a relaxed, deeper vowel, somewhat like the vowel in the second syllable of sofa, but not exactly
• ü is like the German ü or the French u; say ee while rounding your lips

So roughly:

• arkadaşım ≈ ar-ka-da-shum
  but with Turkish ı, not a normal English u
• bugün ≈ boo-GUEN
  with rounded ü sounds

The stress is usually not very strong, but saying the sounds clearly matters more than heavy stress.

Probably these three points:

1. Possession is shown with an ending
   arkadaşım = my friend

2. The additive particle is separate
   da = too / also / either

3. The verb is negative present continuous
   gelmiyor = isn’t coming

So this one sentence is a very useful example of three common Turkish patterns at once.