Gece komodinin üstüne telefonumu ve gözlüğümü koyuyorum.

In Turkish, some time words can be used on their own as adverbs. Here, gece means at night / during the night.

So:

• Gece = at night
• Sabah = in the morning
• Akşam = in the evening

This is a common and natural usage. In other contexts, you might also see forms like geceleri meaning at nights / at night regularly.

Because üstü/üstüne is being used in a possessed construction.

Turkish often expresses on top of the nightstand as:

• komodinin üstü = the top/surface of the nightstand
• komodinin üstüne = onto the top/surface of the nightstand

Here:

• komodin = nightstand
• komodinin = of the nightstand
• üstüne = onto its top / onto the top

So literally, the phrase works like onto the nightstand’s top.

This structure is very common in Turkish:

• masanın üstü = the top of the table
• sandalyenin arkası = the back of the chair
• evin önü = the front of the house

Üstüne means onto / on top of.

It comes from:

• üst = top, upper part
• üstü = its top / the top of it
• üstüne = onto its top / onto the top

The ending -e / -a here is the dative case, which often gives the idea of movement toward something.

So:

• komodinin üstünde = on the nightstand (location, no movement)
• komodinin üstüne = onto the nightstand (movement toward that place)

Since koymak means to put/place, movement is involved, so üstüne is the right choice.

They take endings because they are:

1. possessed: my phone, my glasses
2. definite direct objects: the specific things being placed

Let’s break one down:

• telefon = phone
• telefonum = my phone
• telefonumu = my phone (as a definite direct object)

And:

• gözlük = glasses / eyeglasses
• gözlüğüm = my glasses
• gözlüğümü = my glasses (as a definite direct object)

With koymak (to put), the thing being put is usually a direct object. Since these are specific items, Turkish uses the accusative ending.

This is due to a common sound change in Turkish.

When some words ending in k take a vowel-starting ending, the k often changes to ğ.

So:

• gözlük
  • -üm → gözlüğüm = my glasses
• gözlüğüm
  • -ü → gözlüğümü = my glasses (object)

This happens in many words:

• köpek → köpeğim
• renk → rengim
• çocuk → çocuğum

So gözlüğümü is the expected form.

Both can relate to present time or habits, but they are used differently.

• koyuyorum = I am putting / I put
• koyarım = I put / I usually put / I would put

In everyday Turkish, -yor often covers both:

• an action happening now
• a habitual action, depending on context

So Gece ... koyuyorum can naturally mean At night, I put ...

If you said koyarım, it would sound more like:

• a general habit
• a characteristic action
• sometimes a slightly more detached or matter-of-fact statement

For many learners, the important point is: Turkish often uses -yor where English would use a simple present for routine actions.

Because the verb already shows the subject.

• koyuyorum = I am putting / I put

The ending -um tells us the subject is I.

Turkish often leaves out subject pronouns when they are already clear from the verb:

• geliyorum = I am coming
• gidiyorsun = you are going
• yapıyor = he/she/it is doing

You can add ben for emphasis, but it is not necessary:

• Ben gece komodinin üstüne telefonumu ve gözlüğümü koyuyorum.

Turkish usually puts the verb at the end of the sentence.

So the structure here is roughly:

• Gece = at night
• komodinin üstüne = onto the nightstand
• telefonumu ve gözlüğümü = my phone and my glasses
• koyuyorum = I put / I am putting

This is very normal Turkish word order.

A common default pattern is:

time + place + object + verb

English and Turkish organize sentences differently, so the Turkish sentence may feel backwards at first, but it is perfectly natural.

Not in this sentence, if you mean I put them onto the nightstand.

Use:

• üstüne when there is movement toward the place
• üstünde when something is already located there

Compare:

• Telefonumu komodinin üstüne koyuyorum.
  = I put my phone onto the nightstand.

• Telefonum komodinin üstünde.
  = My phone is on the nightstand.

Since koymak involves placing something somewhere, üstüne is the correct form.

In Turkish, gözlük usually means glasses / a pair of eyeglasses as a single item.

So:

• gözlük = glasses
• gözlüğüm = my glasses
• gözlüğümü = my glasses (object form)

Even though English uses a plural-looking word glasses, Turkish treats gözlük as a singular noun in grammar.

In Turkish, each direct object normally keeps its own necessary endings.

So both nouns show:

• possession: my
• accusative: definite direct object

That is why you get:

• telefonumu
• gözlüğümü

not just one marked noun for the pair.

This is the natural Turkish way to say my phone and my glasses when both are objects of the verb.

Yes, it often can, depending on context.

Because the sentence uses koyuyorum, the whole sentence can easily be understood as a regular habit:

• At night, I put my phone and glasses on the nightstand.

If you wanted to make the habitual meaning more explicit, you could say things like:

• Her gece = every night
• Geceleri = at nights / at night regularly

So:

• Gece ... koyuyorum = natural, can imply a nighttime habit
• Her gece ... koyuyorum = more clearly every night