Post hiemem ver venit, et puellae flores in horto iterum vident.

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

• hiems = winter
• accusative singular = hiemem
• so post hiemem = after winter

This is something you often just have to memorize with prepositions in Latin: each preposition regularly takes a particular case.

Ver is nominative singular because it is the subject of venit.

• ver = spring
• venit = comes

So ver venit means spring comes.

A learner might expect a more obvious ending, but ver is a neuter noun, and its nominative singular form is simply ver.

It is singular because its subject, ver, is singular.

• ver = one spring
• venit = he/she/it comes or simply comes

In Latin, verbs must agree with their subjects in person and number. Since ver is singular, the verb is singular too.

Here puellae means the girls and is nominative plural.

That form can be confusing, because puellae can also be:

• genitive singular = of the girl
• dative singular = to/for the girl
• nominative plural = girls

We know it is nominative plural here because it goes with the plural verb vident:

• puellae ... vident = the girls see

Because flores is the direct object of vident.

• vident = they see
• what do they see? flores = flowers

So flores must be in the accusative plural.

Its dictionary form is flos, and the accusative plural is flores.

Because here in means in or inside, showing location, not motion toward.

Latin uses:

• in + ablative for location: in horto = in the garden
• in + accusative for motion into: in hortum = into the garden

So if the girls are already there and seeing flowers in the garden, Latin uses the ablative: in horto.

Iterum means again. It is an adverb.

Adverbs in Latin are often fairly flexible in position, so iterum can appear in different places depending on emphasis. Here it comes near vident:

• puellae flores in horto iterum vident
• the girls see flowers in the garden again

Even though English adverb placement can be quite fixed, Latin often allows more freedom.

Because Classical Latin does not have a definite article like English the, or an indefinite article like a/an.

So:

• puellae can mean girls or the girls
• flores can mean flowers or the flowers
• horto can mean garden or the garden

You figure out which is best from the context and the translation.

Latin word order is much more flexible than English word order because Latin uses case endings to show grammatical function.

English depends heavily on position:

• the girls see the flowers is different from the flowers see the girls

Latin can move words around more freely because endings show who is doing what.

In this sentence:

• Post hiemem ver venit
• et puellae flores in horto iterum vident

the order is perfectly natural. A more English-like order is possible, but Latin often places words for emphasis, rhythm, or style, not just strict subject-verb-object order.

Because videre belongs to the 3rd conjugation, and its 3rd person plural present active ending is -unt, attached in a way that gives vidunt? No—its correct form is vident.

Here is the pattern:

• video = I see
• vides = you see
• videt = he/she/it sees
• videmus = we see
• videtis = you all see
• vident = they see

So puellae ... vident means the girls see.

It is placed first to set the scene: after winter.

Latin often puts a time phrase early in the sentence to give the context before the main action. So the sentence begins by establishing when the action happens, and then moves to the main idea:

• Post hiemem = after winter
• ver venit = spring comes

That ordering is very natural in Latin.

In some contexts, yes: venit can be either present or perfect in form depending on the verb and context. However, with venio, the forms are usually distinguished:

• present: venit = comes
• perfect: venit is also spelled the same and can mean came or has come

So the form itself can be ambiguous. Here the context makes comes the natural meaning:

• After winter, spring comes
• then a general present statement follows: the girls see flowers in the garden again

So this is best understood as a present-tense sentence about a recurring situation.

We know from both case and verb agreement.

• puellae is nominative plural here, which is the normal case for the subject
• flores is accusative plural, which marks the direct object
• vident is plural, agreeing with puellae

So the structure is:

• puellae = subject = the girls
• flores = object = flowers
• vident = verb = see

That is why the sentence means the girls see flowers, not the flowers see the girls.