Learn Hardcore Latin: Puer quietus domi manet. - The quiet boy stays at home.

manet ends in -t, which marks 3rd person singular in the present tense (he/she/it stays).
The word that matches this in number (singular) and is in the nominative case is the subject.

puer is nominative singular (from the dictionary form puer, pueri, “boy”), so puer is the subject, and manet is the verb:

puer = subject (“the boy” / “a boy”)
manet = verb (“stays”, “remains”)

What exactly is quietus doing in this sentence?

quietus is an adjective meaning “quiet, calm, at rest,” and it is in the nominative masculine singular, agreeing with puer.

Syntactically, it can be understood in two closely related ways:

Attributive adjective: “the quiet boy stays at home.”
- Here it just describes which boy we’re talking about.
Predicate adjective with a “linking-type” verb: “the boy stays (i.e. remains) quiet at home.”
- Here quietus is more like a result/state of staying: he is quiet while he stays.

Because manere (“to remain, to stay”) often behaves like a linking verb (similar to “to be, become”), many teachers will prefer to explain it as:
puer (subject) – manet (linking verb) – quietus (predicate adjective).

Why does quietus have that particular ending, and how does it agree with puer?

Latin adjectives must agree with the noun they describe in gender, number, and case.

puer is masculine, singular, nominative.
So quietus is also masculine, singular, nominative.

That’s why we see quietus (not quietum, quieta, etc.). Some other examples of agreement:

puella quieta domi manet – “the quiet girl stays at home.”
(feminine nominative singular → quieta)
pueri quieti domi manent – “the quiet boys stay at home.”
(masculine nominative plural → quieti)

The adjective changes its ending to match the noun it describes.

What case is domi, and why doesn’t it look like the dictionary form domus?

domi is in the locative case, which expresses “at (a place).”

Dictionary form: domus, domus (house, home)
Locative: domi = “at home”

Latin has a special locative case used mostly with:

names of cities and small islands (e.g. Romae = “at Rome”)
a few common nouns including domus (“home”), rūs (“the countryside”), humus (“ground”), etc.

For domus:

domi = at home
domum = (to) home, homeward
domo = from home

Why isn’t there a preposition like in in front of domi? Could I say in domo instead?

The locative case domi already contains the idea of “at,” so you normally don’t use a preposition with it:

domi = “at home” (no preposition)

You can say in domo, which is grammatically fine and also means “in/at home,” but there is a slight nuance:

domi is the more idiomatic, compact way: “at home” as a general location.
in domo emphasizes “inside the house” (physically in the building).

In early and classical Latin, domi is very common for “at home,” especially in simple sentences like this.

What does manet mean exactly, and what tense and person is it?

manet is from the verb maneo, manēre (“to remain, stay”).

Form of manet:

tense: present
voice: active
mood: indicative
person: 3rd person
number: singular

So manet = “he/she/it stays” or “he/she/it remains.”

In this sentence, with puer as the subject, it means “the boy stays” or “the boy remains.”

Why is there no word for “is” (like est) between puer and quietus?

Latin often doesn’t need a separate est (“is”) when another verb can serve as a linking verb to the adjective.

Here, manet (“remains, stays”) already works as a link between puer and quietus:

puer – subject
manet – “remains” (acts like “is remaining”)
quietus – what he remains (quiet)

So the idea “the boy is quiet” is wrapped into puer quietus manet:

Literally: “the boy remains quiet at home.”
We don’t need puer est quietus et domi manet unless we want to emphasize two separate statements: “The boy is quiet, and he stays at home.”

Could the word order be different, like Puer domi quietus manet or Domi puer quietus manet?

Yes. Latin word order is flexible, and all of these are possible and grammatical:

Puer quietus domi manet
Puer domi quietus manet
Domi puer quietus manet
Quietus puer domi manet, etc.

Because case endings tell you the roles of the words (puer is nominative, domi is locative, etc.), Latin doesn’t rely on a fixed Subject–Verb–Object order the way English does.

Changes in word order usually affect emphasis or style, not the basic meaning. For a learner, the original sentence is quite straightforward: subject (puer) near the beginning, verb (manet) at the end.

Does quietus here mean “quietly”? How would you say “The boy stays quietly at home”?

No. quietus is an adjective (“quiet, calm”), not an adverb (“quietly”).

quietus = quiet (describes a noun: a quiet boy)
quiete (or quietē, depending on your spelling tradition) = quietly (describes a verb: stays quietly)

So:

Puer quietus domi manet = “The boy is (or remains) quiet at home” / “The quiet boy stays at home.”
Puer quiete domi manet = “The boy stays quietly at home.”

In the original sentence, the focus is on the state of the boy (he is quiet), not on the manner of staying.

Why doesn’t Latin show “the” or “a” before puer? How do we know whether to translate it as “the boy” or “a boy”?

Classical Latin has no separate words for “the” or “a/an”. Context decides whether a noun is definite or indefinite.

So puer by itself can be translated as:

“a boy” (introducing him for the first time, or when he’s not specific)
“the boy” (when the boy is already known or specific in the context)

In isolation, Puer quietus domi manet could be translated either way. In a real passage:

If a boy has already been mentioned, you’d usually use “the boy”.
If this is the first time we hear about him, “a boy” is often more natural in English.

Latin leaves that nuance to context; English supplies “the” or “a” when translating.