La ligamento ne estas parto de la spino.

In Esperanto, -o marks a noun.

So in this sentence:

• ligamento = ligament
• parto = part
• spino = spine

This makes Esperanto very regular: when you see -o, you can immediately recognize the word as a noun.

La is the Esperanto definite article, meaning the.

So:

• la ligamento = the ligament
• la spino = the spine

Esperanto uses la for all genders and numbers. It never changes form.

Also, Esperanto has no indefinite article, so there is no separate word for a or an.
For example:

• ligamento = a ligament / ligament
• la ligamento = the ligament

In Esperanto, ne normally comes before the word it negates.

Here it negates the verb phrase:

• ne estas = is not

So:

• La ligamento ne estas parto de la spino.
• The ligament is not part of the spine.

This is the normal and most natural placement.

Estas means is / are / am.

One very helpful feature of Esperanto is that the verb does not change depending on the subject.

For example:

• mi estas = I am
• vi estas = you are
• li estas = he is
• ili estas = they are

So estas stays the same for everyone.

Parto de la spino literally means part of the spine.

The preposition de often shows possession, relationship, or of-meaning:

• la pordo de la domo = the door of the house
• parto de la korpo = part of the body

You could form adjective-based expressions in Esperanto, but parto de la spino is the straightforward and natural way to say part of the spine.

De usually means of, from, or shows a relationship between two nouns.

In this sentence:

• parto de la spino = part of the spine

So de links parto and la spino.

It answers the question: a part of what?
Answer: of the spine.

The -n ending in Esperanto usually marks the direct object or sometimes direction.

In this sentence, there is no direct object.

• La ligamento is the subject.
• estas parto is a linking structure, like is a part.
• de la spino is a prepositional phrase.

Because of that, no accusative -n is needed.

Yes, ligamento is singular: ligament.

To make a noun plural in Esperanto, add -j:

• ligamento = ligament
• ligamentoj = ligaments

So the plural version would be:

• La ligamentoj ne estas partoj de la spino.
• The ligaments are not parts of the spine.

Notice that parto also becomes partoj in the plural.

A simple pronunciation guide is:

• La = lah
• ligamento = lee-gah-MEN-toh
• ne = neh
• estas = ES-tahs
• parto = PAR-toh
• de = deh
• la = lah
• spino = SPEE-noh

A key rule in Esperanto is that stress almost always falls on the second-to-last syllable:

• ligaMENto
• EStas
• PARto
• SPIno

Esperanto word order is fairly flexible, but this sentence uses the most neutral order:

• La ligamento ne estas parto de la spino.

You may sometimes see variations for emphasis, but beginners should stick with the standard pattern:

subject + ne + verb + complement

That will sound natural in most cases.

In this sentence, spino means spine/backbone.

As often happens between languages, meanings may overlap strongly without being identical in every possible context. But for a learner, it is perfectly fine to understand spino here as spine.

Because Esperanto forms negation very regularly:

• estas = is
• ne estas = is not

This is simpler than in English, where forms like is not, are not, do not, does not, and did not all behave differently.

In Esperanto, you usually just add ne before the verb or the part you want to negate.

Not exactly as written.

Because the sentence begins with La ligamento, it specifically says the ligament.

If you wanted a more general or indefinite sense like a ligament, you would normally leave out la:

• Ligamento ne estas parto de la spino.

However, whether that sounds natural depends on context. Very often, Esperanto uses or omits la based on whether the speaker has a specific thing in mind.