Ez a szövetség nagy.

• Ez = this
• a = the
• szövetség = alliance, federation, or union depending on context
• nagy = big or large

So the whole sentence means This alliance is big.

Yes, in a way it does.

In Hungarian, when this or that comes before a noun, it is normally followed by the definite article:

• ez a ház = this house
• ez a szövetség = this alliance

So ez a szövetség is the normal Hungarian way to say this alliance.

This is different from English, where we do not say this the alliance.

In Hungarian, the verb to be is often left out in the present tense when the subject is third person and the sentence is simple:

• Ez a szövetség nagy. = This alliance is big.
• A ház kicsi. = The house is small.

So Hungarian does not need a separate word for is here.

But in other persons, the verb appears:

• Én nagy vagyok. = I am big.
• Te nagy vagy. = You are big.

So this omission is a normal grammar rule, not a special feature of this sentence only.

Because here nagy is part of the predicate: it is saying what the alliance is like.

• Ez a szövetség nagy. = This alliance is big.

When an adjective comes before a noun, it directly describes the noun:

• a nagy szövetség = the big alliance

So the difference is:

• a nagy szövetség = a noun phrase, the big alliance
• A szövetség nagy. = a full sentence, The alliance is big

This is very similar to English:

• the big alliance
• the alliance is big

This word order is neutral and natural.

Hungarian word order is more flexible than English, but changes often add emphasis or focus.

Neutral:

• Ez a szövetség nagy.

If you change the order, the meaning may still be similar, but the emphasis changes. For a beginner, it is best to learn this version as the standard one.

So yes, the sentence is correct and natural as given, but Hungarian does allow other orders in the right context.

Hungarian has two forms of the definite article:

• a
• az

Which one you use depends on the sound that follows:

• a before a consonant sound
• az before a vowel sound

Since szövetség starts with sz, which is a consonant sound, Hungarian uses:

• a szövetség

If the next word started with a vowel, you would use az:

• az alma = the apple

A few useful pronunciation points:

• sz is pronounced like English s in see
• s by itself in Hungarian sounds more like English sh
• ö is a rounded front vowel, somewhat like German ö or French eu
• gy is a soft consonant, roughly like the dy sound in duke in some pronunciations, though not exactly

So:

• szövetség is roughly suh-vet-shayg or sö-vech-shayg, depending on how approximate you want to be
• nagy is roughly nody or nawdy, but with a soft gy sound at the end

If you want to sound more natural, it helps to listen to native audio, because ö and gy are not exact English sounds.

Szövetség is a singular noun.

In this sentence:

• ez a szövetség is the subject
• nagy is the predicate adjective

There is no special case ending here; szövetség is in its basic dictionary form.

That makes this sentence a good beginner example, because it shows a very common Hungarian pattern:

• [demonstrative + article + noun] + [adjective]

For example:

• Ez a könyv érdekes. = This book is interesting.
• Ez a város nagy. = This city is big.

Yes.

Ez by itself means this:

• Ez nagy. = This is big.

But if you want to say this alliance, you normally use:

• ez a szövetség

So:

• Ez nagy. = This is big.
• Ez a szövetség nagy. = This alliance is big.

The longer version is more specific because it names the noun directly.