Tandroden ligger under tandkødet.

Because Danish, like English, often makes compound nouns by joining words together.

• tand = tooth
• rod = root
• tandrod = tooth root

Then the definite ending is added:

• tandrod = a tooth root
• tandroden = the tooth root

This is very common in Danish. English sometimes writes similar ideas as two words, but Danish often prefers one combined word.

The ending -en is the definite article attached to the noun. It means the.

So:

• en tandrod = a tooth root
• tandroden = the tooth root

In Danish, the definite article is usually added to the end of the noun instead of being a separate word like English the.

Because tandkød is a neuter noun.

Danish nouns have two grammatical genders:

• common gender → usually takes en / -en
• neuter gender → usually takes et / -et

So:

• en tandrod → tandroden
• et tandkød → tandkødet

That is why the two nouns in the sentence take different definite endings.

It usually refers to the gum tissue in general, so in English it is often best translated as the gums even though Danish uses a singular-looking form.

• tandkød is more like a mass noun
• it refers to gum tissue as a whole, not usually to one separate gum

So under tandkødet means under the gums or under the gum tissue.

Danish often uses ligge when something is located somewhere physically, especially when it is understood as resting or being situated in a place.

So:

• Tandroden ligger under tandkødet. = The tooth root is located under the gums.

Using er would focus more on simple identity or existence, while ligger sounds more natural for physical position here.

This is a very common difference between Danish and English.

No. In Danish, ligge is used much more broadly than English lie.

It can describe:

• things physically lying down
• things resting somewhere
• places or objects being situated somewhere

Examples:

• Bogen ligger på bordet. = The book is on the table.
• København ligger på Sjælland. = Copenhagen is on Zealand.

So in your sentence, ligger does not mean the tooth root is literally lying down in a dramatic way. It just means it is located there.

Under means under / beneath.

It is a very straightforward preposition in this sentence:

• under tandkødet = under the gums

It works much like English under.

Because Danish usually puts the at the end of the noun as a suffix.

Compare:

• English: the tooth root

• Danish: tandroden

• English: the gum(s)
• Danish: tandkødet

A separate definite word can appear in Danish too, but usually only when there is an adjective or some other modifier:

• tandroden = the tooth root
• den betændte tandrod = the inflamed tooth root

So in your sentence, no separate the is needed.

This sentence has normal Danish word order:

• Tandroden = subject
• ligger = verb
• under tandkødet = prepositional phrase

So the pattern is:

Subject + Verb + Place

That is very natural in a simple statement.

You would use the indefinite form of tandrod:

• En tandrod ligger under tandkødet.

Compare:

• tandroden = the tooth root
• en tandrod = a tooth root

Notice that tandkødet stays definite here, because you are still talking about the gums as a specific body part.

Grammatically, it is singular definite:

• tandroden = the tooth root

So it literally refers to the tooth root. Depending on context, Danish can use a singular definite form to describe anatomy in a general explanatory way, especially in educational or medical contexts.

If you wanted a clearly plural version, you could say:

• Tandrødderne ligger under tandkødet. = The tooth roots lie under the gums.

A rough pronunciation guide is:

• tandroden ≈ TAN-droh-thən
• tandkødet ≈ TAN-køh-thəth or TAN-køh-ðəð depending on pronunciation style

A few useful points:

• ø is a vowel that does not exist in standard English
• it is somewhat similar to the vowel in French deux or German schön
• the d in Danish is often soft, especially between vowels or after certain sounds

You do not need perfect pronunciation right away, but ø is definitely worth practicing because it appears in many common Danish words.

Usually yes. Tandrod is a very transparent compound:

• tand = tooth
• rod = root

So tandrod = tooth root

But as always, in real context the best English translation may sometimes be slightly different depending on whether the text is medical, educational, or everyday language. In this sentence, tooth root is a very natural translation.