Ziua este specială.

Because Romanian usually puts the definite article at the end of the noun, not as a separate word before it.

• zi = day
• ziua = the day

So -a here is the definite article for this feminine singular noun.

This is very different from English, where you would say the day with a separate word.

Romanian often uses a postposed definite article, which means the article is attached to the noun itself.

So instead of:

• English: the day

Romanian uses:

• ziua

This is one of the most important structural differences between English and Romanian.

A few similar examples:

• fată = girl

• fata = the girl

• băiat = boy
• băiatul = the boy

Yes. Zi is feminine in Romanian.

That matters because:

• the definite article changes according to gender
• adjectives must agree with the noun

So:

• zi is feminine
• ziua is the day
• specială is also in the feminine singular form to match it

Because adjectives in Romanian must agree with the noun in gender and number.

Since ziua is feminine singular, the adjective must also be feminine singular:

• masculine singular: special
• feminine singular: specială

So:

• băiatul este special = the boy is special
• ziua este specială = the day is special

Este is the 3rd person singular present tense form of a fi, which means to be.

So:

• eu sunt = I am
• tu ești = you are
• el/ea este = he/she is

In Ziua este specială, este means is.

Yes. E is a very common short form of este.

So both are correct:

• Ziua este specială.
• Ziua e specială.

The version with e is more common in everyday speech.
The version with este may sound a little more careful, explicit, or formal depending on context.

Normally, no. In standard Romanian, you usually keep the verb a fi in this kind of sentence.

So you say:

• Ziua este specială.
• Ziua e specială.

Not normally just:

• Ziua specială. for The day is special

That shorter form would usually mean something more like the special day, not a full sentence with is.

It is usually pronounced about like ZEE-wa.

A helpful breakdown:

• zi sounds like zee
• ua here sounds like wa

So the whole word is roughly:

• ziua = ZEE-wa

It has two syllables:

• zi-wa

Roughly like spe-cha-luh, with the stress on the second syllable:

• spe-ci-a-lă

A few useful pronunciation points:

• ci before a sounds like ch
• ă is the Romanian mid-central vowel, often approximated by a weak uh sound

So specială is roughly:

• spe-CHA-luh

Yes, Romanian word order is somewhat flexible, but Ziua este specială is the most neutral and natural basic order.

Other orders are possible for emphasis, such as:

• Specială este ziua.
• Ziua specială este... if continuing into something else

But for a learner, the safest default is:

• subject + este/e + adjective
• Ziua este specială.

If you want a day is special or it is a special day, the structure changes.

Compare:

• Ziua este specială. = The day is special.
• Este o zi specială. = It is a special day.

Here:

• o zi = a day
• specială still agrees with zi, so it stays feminine singular

So ziua is definite, while o zi is indefinite.

It is in the nominative, because it is the subject of the sentence.

In this sentence:

• ziua = the subject
• este = the verb
• specială = the predicate adjective

So the structure is basically:

• Ziua = subject
• este specială = is special

For a beginner, the key point is simply that ziua is the thing being described.