Fabrikanın yeni cihazları bugün test edildi.

Because -ın / -in / -un / -ün is the genitive ending, often translated as of or 's.

• fabrika = factory
• fabrikanın = the factory’s / of the factory

So fabrikanın yeni cihazları means the factory’s new devices.

The exact vowel in the ending changes by vowel harmony. Here it is -nın because the noun ends in a vowel and the correct vowel is ı:

• fabrika + nın → fabrikanın

Because this noun is part of a possessive construction.

In fabrikanın yeni cihazları:

• fabrikanın = the factory’s
• cihazları = its devices

Turkish usually marks both parts of this kind of phrase:

1. the possessor gets the genitive ending
2. the possessed noun gets a possessive ending

So:

• cihaz = device
• cihazlar = devices
• cihazları = its devices / the devices of it

Here the ending on cihazları is showing that the devices belong to the factory.

By itself, cihazları can be ambiguous in some contexts, but in this sentence it clearly means its devices / the factory’s devices because it follows fabrikanın.

Possible meanings of cihazları in different contexts can include:

• its/his/her devices
• sometimes the devices in certain structures
• sometimes an accusative form depending on context

But once you see fabrikanın ... cihazları, the meaning is straightforward: the factory’s devices.

Turkish does not have a direct equivalent of the English article the.

So Turkish often expresses definiteness through:

• context
• word order
• possessive structures
• case endings

In fabrikanın yeni cihazları, English naturally uses the:

• the factory’s new devices

But Turkish does not need a separate word for it.

Yeni means new, and it modifies cihazları.

So:

• fabrikanın = the factory’s
• yeni = new
• cihazları = devices

Together: fabrikanın yeni cihazları = the factory’s new devices

Like English, Turkish adjectives come before the noun:

• yeni cihazlar = new devices
• büyük bina = big building

And unlike nouns, adjectives do not change form for plural.

Because test etmek is a common Turkish verb made with a noun plus etmek.

• test = test
• test etmek = to test

In the passive, this becomes:

• test edilmek = to be tested

And in the past tense:

• test edildi = was/were tested

So this is not unusual at all. Turkish has many expressions like this:

• kontrol etmek = to check
• ilan etmek = to announce
• fark etmek = to notice

And their passive forms:

• kontrol edildi = was checked
• ilan edildi = was announced

Because Turkish verbs usually do not have separate singular and plural forms in the past tense the way English does.

So:

• Cihaz test edildi. = The device was tested.
• Cihazlar test edildi. = The devices were tested.

The verb form edildi stays the same.

English changes was / were, but Turkish does not need that distinction here.

Yes, it is passive.

The active idea would be something like:

• They tested the factory’s new devices today.

The Turkish sentence says:

• Fabrikanın yeni cihazları bugün test edildi.
• The factory’s new devices were tested today.

You can tell it is passive because etmek becomes edilmek:

• test etmek = to test
• test edilmek = to be tested

Then edildi is the past tense:

• was/were tested

So the sentence focuses on the devices, not on who did the testing.

It is the simple past tense in the passive.

• edil- = be done / be subjected to
• -di = past tense

So test edildi means:

• was tested
• were tested

Depending on the subject.

In this sentence, since the subject is plural (cihazları), the natural English translation is:

• were tested

Bugün means today, and its position is very natural in Turkish.

The sentence structure is:

• Fabrikanın yeni cihazları = the factory’s new devices
• bugün = today
• test edildi = were tested

So: Fabrikanın yeni cihazları bugün test edildi.

This is a very normal word order: subject + time + verb.

Turkish word order is flexible, but the verb often comes at the end. You could move bugün for emphasis, but the given sentence is neutral and natural.

Yes, Turkish allows some flexibility, especially for emphasis.

For example, these are possible:

• Fabrikanın yeni cihazları bugün test edildi.
  Neutral: The factory’s new devices were tested today.

• Bugün fabrikanın yeni cihazları test edildi.
  Slightly stronger focus on today.

• Test edildi bugün fabrikanın yeni cihazları.
  Grammatically possible in special contexts, but much less neutral and much less common in ordinary speech.

The most standard version is the one you were given, with the verb at the end.

Cihaz most often means device, instrument, or apparatus, depending on context.

So cihazları could be translated in different ways:

• devices
• equipment
• units
• sometimes machines, if the context supports it

In a factory context, devices is a safe and literal translation, but in real-world English you might also hear:

• The factory’s new equipment was tested today.

That said, the Turkish sentence itself is singular/plural with cihazlar, so devices matches the grammar closely.

Because Turkish verbs generally do not need plural marking to match a plural subject in this kind of sentence.

English says:

• The device was tested
• The devices were tested

Turkish says:

• Cihaz test edildi
• Cihazlar test edildi

Same verb form.

So the plurality is already clear from cihazları. Turkish does not need an extra plural form on the verb here.

No, not in this exact form.

Fabrikanın yeni cihazları bugün test edildi is passive:

• The factory’s new devices were tested today

If you want The factory tested its new devices today, you would need an active sentence, such as:

• Fabrika yeni cihazlarını bugün test etti.

Notice the difference:

• cihazları = its devices / the factory’s devices
• cihazlarını = its devices as a definite direct object

And:

• test edildi = were tested
• test etti = tested

So the original sentence is clearly passive, not active.