Learn Hardcore Latin: Puer manus et pedes lavat, et mater caput eius spectat. - The boy washes his hands and feet, and mother looks at his head.

Puer is nominative singular, meaning “boy” as the subject of the verb.
It belongs to the second declension, but some masculine nouns in this declension end in -er in the nominative singular (like puer, ager, etc.) instead of -us.

So:

puer = boy (subject, singular)
not puerus (a form that doesn’t exist).

Are manus and pedes singular or plural, and how can I tell?

In this sentence both are plural:

manus = hands (accusative plural)
pedes = feet (accusative plural)

Pedes is easier: it comes from pēs, pedis (m., 3rd decl.).

pēs = foot (nom. sg.)
pedem = foot (acc. sg.)
pedēs = feet (nom. OR acc. pl.)

Since pedes goes with lavat as something being washed, it must be accusative plural (“washes [the] feet”).

Manus is trickier because manus, manūs (f., 4th decl.) has several forms that look like manus:

manus = hand (nom. sg.)
manūs = of the hand (gen. sg.)
manūs = hands (nom. OR acc. pl.)

Here manus is also a thing being washed, so it too is accusative plural: “(his) hands.”

What cases are manus, pedes, and caput, and why those cases?

All three are in the accusative case because they are direct objects of the verbs:

Puer manus et pedes lavat
- manus = “hands” → object of lavat
- pedes = “feet” → object of lavat
et mater caput eius spectat
- caput = “head” → object of spectat

Latin marks direct objects with the accusative, so all the body parts here appear in the accusative.

Why is there no word for “his” before manus et pedes?

Latin usually does not use a possessive pronoun with parts of the body (or with very close possessions) when the owner is clear from the context.

“Puer manus et pedes lavat” literally is “The boy washes hands and feet,” but Latin automatically understands these as his own hands and feet. Adding suās manus et pedes would usually sound unnecessarily heavy or emphatic.

So:

Latin: Puer manus et pedes lavat.
Natural English: The boy washes his hands and feet.

Why do we have eius with caput, and what exactly does eius mean?

Eius is the genitive singular of the 3rd-person pronoun is, ea, id, and it means “of him / of her / of it”, which in English we normally translate as “his / her / its”.

So:

caput eius = “the head of him” → “his head”

We need eius here because otherwise caput could be anyone’s head. Eius tells us whose head is being looked at.

Why is it eius and not suus / suum, and who does eius refer to here?

Latin distinguishes between:

reflexive possessive: suus, sua, suum = “his/her/its/their own” (referring to the subject of that clause)
non‑reflexive possessive: eius (sg.), eōrum / eārum (pl.) = “his/her/its/their” (referring to someone else)

In et mater caput eius spectat:

the subject is mater (the mother),
eius refers not to the mother, but to someone else → here, the boy.

So eius here means “his (the boy’s) head”, not “her (own) head.”
If the mother were looking at her own head (strange, but grammatically possible), Latin would use the reflexive:

mater caput suum spectat = “the mother looks at her own head.”

Could eius also mean “her” instead of “his”?

Yes. Eius does not show grammatical gender; it can mean:

his
her
its

The exact English translation depends on the context: whose thing is being talked about.
Here, because the story mentions a boy and a mother, and the second clause introduces the mother as the new subject, eius naturally points back to the boy: “his (the boy’s) head.”

Why isn’t there a separate word for “he” or “she” in this sentence?

Latin usually omits personal subject pronouns (ego, tu, is, etc.) because the verb ending already shows the person and number.

lavat = “he/she/it washes”
spectat = “he/she/it looks at”

The subject nouns themselves (here puer and mater) tell you exactly who is doing the action, so adding is (“he”) or ea (“she”) would normally be redundant.

So Latin:

Puer... lavat, et mater... spectat.

English needs the pronouns:

He washes… and she looks…
but Latin usually does not.

What tense and person are lavat and spectat, and how can I see that?

Both verbs are:

3rd person singular
present tense
active voice
indicative mood

Forms:

lavat = he/she/it washes (from lavō, lavāre)
spectat = he/she/it looks at (from spectō, spectāre)

You can see 3rd person singular from the -t ending in the present indicative active:

lavo (I wash)
lavas (you wash)
lavat (he/she/it washes)

Why does manus end in -us if it is feminine?

Manus belongs to the fourth declension, where many nouns have -us endings regardless of gender. In that declension:

manus, manūs is feminine, meaning “hand.”
The -us ending in the nominative singular does not guarantee masculine gender in Latin; gender is a separate property that you must learn with the noun.

So:

manus = hand, feminine, 4th declension
Endings like -us are not reliable gender markers by themselves.

Could manus be nominative here instead of accusative, and how do we know it isn’t?

Formally, manus could be nominative plural or accusative plural (or genitive singular). The form alone doesn’t decide it.

But in the sentence:

Puer manus et pedes lavat

we already have a clear subject in the nominative: puer.
Lavat is a transitive verb (it needs an object), so the words after it that are being washed are naturally in the accusative:

manus and pedes must be objects, so they are accusative plural, not nominative.

Why is the order caput eius spectat and not eius caput spectat or spectat caput eius?

Latin word order is flexible. The basic information is given by endings, not position, so several orders are possible:

mater caput eius spectat
mater eius caput spectat
mater spectat caput eius

All can mean essentially the same thing: “the mother looks at his head.”

The version caput eius spectat puts caput eius together as a unit (“his head”) before the verb, which can give that phrase slightly more focus or emphasis. But syntactically, all the orders are acceptable; the choice is more about style and nuance than about grammar.

Why do we see et twice, and what is the difference between the two et’s?

There are two different connections here:

manus et pedes
- This et joins two objects of the same verb lavat:
- “hands and feet”
..., et mater caput eius spectat
- This et joins two clauses (two separate subject–verb groups):
- “The boy washes his hands and feet, and the mother looks at his head.”

So both are the same word et = “and”, but:

the first connects nouns,
the second connects sentences/clauses.

How would I say “The boy washes his hands and feet and looks at his own head” when all actions refer to the boy?

To say that the boy himself both washes and looks at his own head, Latin would normally use the reflexive possessive suus:

Puer manus et pedes lavat et caput suum spectat.

Here:

puer is the only subject,
suum refers back to that same subject,
so the meaning is: “The boy washes his hands and feet and looks at his own head.”

In the original sentence, eius was used because in the second clause the subject changed to mater, and eius had to refer back to someone else (the boy).