Puer manus et pedes lavat, et mater caput eius spectat.

The boy washes his hands and feet, and mother looks at his head.

Breakdown of Puer manus et pedes lavat, et mater caput eius spectat.

• puer: the boy
• et: and
• mater: the mother
• spectare: to look at

Questions & Answers about Puer manus et pedes lavat, et mater caput eius spectat.

Is puer singular or plural, and why isn’t it puerus?

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