Thalamus floribus ornatur.

Because thalamus is in the nominative singular, the case normally used for the subject.

Also, the verb ornatur is third person singular, so it matches a singular subject: thalamus.

So the basic structure is:

• thalamus = the thing being talked about
• ornatur = is adorned / is decorated

In other words, thalamus is the thing that is being adorned.

Ornatur comes from the verb orno, ornare, meaning to adorn, decorate, equip, embellish.

Here, ornatur means:

• is adorned
• is decorated
• literally, is being adorned

Grammatically, it is:

• present tense
• passive voice
• third person singular

A very useful clue is the ending -tur, which often marks the third person singular passive in Latin.

The sentence focuses on the room/chamber as the thing receiving the action, not on the person doing the decorating.

So instead of saying:

• Someone decorates the chamber with flowers

Latin says:

• The chamber is decorated with flowers

This is very common in Latin. If the doer of the action is unimportant or not mentioned, the passive is often preferred.

Floribus is ablative plural of flos, floris, meaning flower.

It is in the ablative because it expresses the means or instrument by which something is adorned:

• floribus = with flowers

This is called the ablative of means or ablative of instrument.

So:

• Thalamus floribus ornatur = The chamber is adorned with flowers

Because Latin often uses the bare ablative to express means or instrument, especially with inanimate things.

So Latin can simply say:

• floribus = with flowers

without adding a separate word for with.

This is normal Latin usage. English needs with, but Latin often does not.

Usually, in a sentence like this, floribus by itself is the more natural choice.

Why? Because flowers here are the means by which the chamber is decorated, and Latin commonly uses the ablative without a preposition for that.

Cum is more often used when the meaning is more like together with or simple accompaniment, especially with people.

So in this sentence, floribus alone is the standard and expected form.

It is present tense.

So it can mean:

• is adorned
• is being adorned
• gets adorned in some contexts

In simple translation, English usually says is adorned or is decorated.

Because Latin does not have articles like English the and a/an.

So a noun like thalamus can mean:

• a chamber
• the chamber

and the exact sense comes from context.

Likewise, floribus can mean simply with flowers, and English adds whatever article sounds natural.

In Latin, thalamus usually means a chamber, especially an inner room, bedchamber, or often a bridal chamber.

So depending on context, it may be translated in different ways, such as:

• chamber
• bedroom
• bridal chamber

The grammar of the sentence stays the same whichever English word is chosen.

Yes. Latin word order is much more flexible than English word order because the endings show the grammatical roles.

So all of these could mean the same thing:

• Thalamus floribus ornatur
• Floribus thalamus ornatur
• Ornatur thalamus floribus

The choice of order can change emphasis or style, but not the core meaning.

In the original sentence, the order is very natural: subject first, then the ablative phrase, then the verb.

An active version would name the doer of the action. For example:

• Ancilla thalamum floribus ornat = The maid decorates the chamber with flowers
• Feminae thalamum floribus ornant = The women decorate the chamber with flowers

Notice what changes:

• thalamus becomes thalamum because it is now the direct object
• ornatur becomes ornat or ornant, depending on the subject
• floribus stays ablative, because it still means with flowers

The dictionary forms are:

• thalamus, -i = chamber
• flos, floris = flower
• orno, ornare = adorn, decorate

From those forms, we get:

• thalamus = nominative singular
• floribus = ablative plural
• ornatur = present passive, third singular

Learning to connect the sentence forms to the dictionary forms is a big part of reading Latin confidently.