Post cenam panis siccus manet, et puer aquam petit.

Because post is a preposition that takes the accusative case when it means after.

• cena = nominative singular, dinner
• cenam = accusative singular

So:

• post cenam = after dinner

This is something you simply learn with the preposition: post + accusative.

Panis is nominative singular, and it is the subject of manet.

A good clue is the verb:

• manet = he/she/it remains, third person singular

Since the verb is singular, its subject is also singular. In this sentence, panis is the noun that fits as the subject: the bread remains.

Also, panis is a third-declension noun, so its nominative singular does not look like a first- or second-declension noun.

Siccus is an adjective meaning dry, and it must agree with panis in:

• gender
• number
• case

Here:

• panis is masculine
• singular
• nominative

So the adjective must also be:

• masculine
• singular
• nominative

That gives siccus.

As for position, Latin adjectives can come before or after the noun. So panis siccus is perfectly normal Latin for dry bread.

Yes. Panis is a masculine noun, even though its ending may not look familiar to an English speaker.

Not all masculine nouns are second-declension nouns ending in -us. Many third-declension nouns have different endings, and their gender has to be learned from vocabulary.

So when you learn the word, you learn something like:

• panis, panis, m. = bread

The m. tells you it is masculine.

Manet is from the verb maneo, manere, meaning remain, stay, or continue to be.

Here it is:

• present tense
• active voice
• indicative mood
• third person singular

So manet means:

• he remains
• she remains
• it remains

In this sentence, it means it remains, referring to panis.

Because puer is the actual nominative singular form of the noun.

Some second-declension masculine nouns end in -er instead of -us. Puer is one of them.

So:

• puer = boy
• not puerus

Its genitive singular is pueri, which shows it belongs to the second declension.

Because aquam is the direct object of petit.

The boy is asking for or seeking water, so water is the thing directly affected by the verb. In Latin, the direct object is usually put in the accusative case.

So:

• aqua = nominative singular
• aquam = accusative singular

That is why the sentence has puer aquam petit.

Yes, it is related. Petit comes from peto, petere, a verb with a fairly broad range of meanings, including:

• seek
• aim at
• ask for
• request

In this sentence, the most natural meaning is asks for or seeks.

So puer aquam petit means that the boy asks for water or wants water in context.

This is a good reminder that one Latin verb can have several related meanings, and context helps you choose the best English translation.

Latin word order is much more flexible than English word order because the endings show what each word is doing.

English depends heavily on position:

• The boy asks for water is different from Water asks for the boy

Latin can move words around more freely because case endings make the roles clearer.

In your sentence:

• post cenam panis siccus manet
• et puer aquam petit

Latin often places the verb toward the end, and adjectives may come before or after nouns. So the order may feel unusual to an English speaker, but it is normal Latin.

Because Latin does not have definite and indefinite articles like English does.

So a Latin noun like panis can mean:

• bread
• the bread
• a bread

And puer can mean:

• boy
• the boy
• a boy

The exact sense depends on context. English usually has to choose, but Latin often leaves it unstated.

Yes. It is a prepositional phrase expressing time: after dinner.

Latin often uses prepositional phrases to show when something happens:

• post cenam = after dinner
• ante cenam = before dinner

So here post cenam tells you the time setting for what follows: the bread remains dry after dinner, and the boy asks for water.