Mater dicit aquam calidam ad cubiculum portari debere.

Latin often uses an accusative-and-infinitive construction for reported statements instead of a that-clause.

So instead of saying:

• Mother says that hot water must be carried...

Latin says, more literally:

• Mother says hot water to need to be carried...

In this sentence, aquam calidam ... portari debere is the whole reported statement after dicit.

Because it is the subject of the infinitive inside an indirect statement.

In normal Latin, the subject of a finite verb is usually nominative. But in an accusative-and-infinitive construction, the subject of the infinitive goes into the accusative.

So:

• aqua calida portari debet = hot water must be carried
  
  • aqua calida is nominative
• mater dicit aquam calidam portari debere = mother says that hot water must be carried
  
  • aquam calidam is accusative because it is now the subject of the infinitive phrase

Even though hot water is not doing the action in English, it is still the grammatical subject of the passive idea to be carried.

Because calidam is an adjective modifying aquam, and Latin adjectives agree with the nouns they describe in:

• gender
• number
• case

So:

• aquam = accusative singular feminine
• calidam = accusative singular feminine

They match because they belong together: hot water.

Portari is the present passive infinitive of porto, portare, meaning to carry.

So:

• portare = to carry
• portari = to be carried

The ending -ri is a common sign of a passive infinitive in first-conjugation verbs.

They do different jobs.

• debere depends on dicit
• portari depends on debere

So the structure is:

• mater dicit = mother says
• aquam calidam debere = that hot water ought/must
• portari = to be carried

Together, portari debere means to have to be carried or ought to be carried.

A very literal breakdown would be:

• Mother says hot water to ought to be carried

That sounds unnatural in English, but it shows the Latin structure.

Debere can express obligation, so depending on context it may be translated as:

• must
• should
• ought to
• is supposed to

In this sentence, the exact English choice depends on tone and context. If the mother is giving a firm instruction, must works well. If it is milder, ought to or should may fit better.

So portari debere can mean:

• must be carried
• ought to be carried
• should be carried

Because ad with the accusative often shows motion toward a place.

So:

• ad cubiculum = to the bedroom/room
• in cubiculo = in the bedroom/room

Since the water is being carried to the room, ad is appropriate.

It is accusative singular because it follows ad.

The preposition ad takes the accusative and usually means:

• to
• toward
• up to

So:

• ad cubiculum = to the room/bedroom

The sentence does not specify the person who will carry it. That is because the verb is passive:

• portari = to be carried

A passive form lets Latin focus on the action or the thing affected by it, without naming the doer.

If Latin wanted to name the agent, it could do so, often with ab/ā plus the ablative in a full passive construction. But here, the agent is simply left unstated.

Because classical Latin has no articles.

So a noun like mater can mean:

• mother
• a mother
• the mother

And aquam can mean:

• water
• the water
• some water

You figure out the most natural English article from the context.

Yes. Latin word order is much more flexible than English because the endings show each word’s role.

So the sentence could be rearranged in various ways without changing the basic meaning, for example:

• Mater aquam calidam ad cubiculum portari debere dicit.
• Aquam calidam mater ad cubiculum portari debere dicit.

The original order is perfectly natural, but the endings—not the position alone—tell you how the words fit together.

No. Mater is the subject of dicit.

So:

• mater = mother says
• aquam calidam = the subject of the reported statement

This is important because English learners sometimes want mother to control everything in the sentence. But in Latin, after dicit, a new clause begins in infinitive form, and aquam calidam belongs to that clause instead.