Folium de arbore cadit et in terra manet.

Because folium is a neuter second-declension noun, and in this sentence it is the subject.

For a neuter noun like folium, folii:

• nominative singular = folium
• accusative singular = folium

So the form looks the same in both cases. Here it is nominative because the leaf is the thing doing the action: it falls and remains.

Because the preposition de takes the ablative case, and the ablative singular of arbor is arbore.

So:

• dictionary form: arbor = tree
• ablative singular: arbore

That is why Latin says de arbore, not de arbor.

Here de means down from, off, or simply from.

So de arbore cadit means that the leaf falls from the tree or down from the tree.

In Latin, de often suggests movement from a higher place or from the surface of something.

Because in can take two different cases:

• in + ablative = in/on a place, showing location
• in + accusative = into/onto a place, showing motion toward

Here we have in terra, with the ablative, because the sentence is focusing on where the leaf remains: on the ground / in the ground area.

Compare:

• in terra manet = it remains on the ground
• in terram cadit = it falls onto the ground

So terra is ablative here because it is treated as a place where the leaf is.

Because both verbs are:

• present tense
• third person singular
• active
• indicative

The -t ending means he/she/it.

So:

• cadit = it falls
• manet = it remains / stays

The subject is folium, which is singular, so singular verb forms are used.

Because Latin has no articles.

English says:

• the leaf
• a leaf

Latin simply says folium, and the reader understands from context whether it means a leaf, the leaf, or sometimes just leaf in a general sense.

The same is true for:

• arbore = from a tree / from the tree
• terra = on the ground / on earth / in the land, depending on context

Not as much as in English. Latin word order is much freer because the noun endings show grammatical function.

This sentence uses a very natural order:

• Folium = subject first
• de arbore = where it falls from
• cadit = first verb
• et = and
• in terra = where it remains
• manet = second verb

But Latin could rearrange this in other ways without changing the basic meaning, for example:

• De arbore folium cadit
• Folium cadit et manet in terra

Different word orders can shift emphasis, but the endings still tell you what each word is doing.

Arbor is a third-declension feminine noun.

Its main forms are:

• nominative singular: arbor
• genitive singular: arboris
• ablative singular: arbore

That is why after de you see arbore.

A learner often notices that arbor does not follow the same pattern as terra or folium. That is because it belongs to a different declension.

Terra is a first-declension feminine noun.

Some useful forms are:

• nominative singular: terra
• accusative singular: terram
• ablative singular: terra

So in in terra, the noun is ablative singular, because in is being used to show location.

Yes. Et is the normal Latin word for and.

Here it connects the two actions:

• cadit = falls
• manet = remains

So the sentence describes a sequence:

1. the leaf falls from the tree
2. and it remains on the ground

Because Latin, like English, does not need to repeat the subject when it is clearly the same.

So:

• Folium de arbore cadit et in terra manet

means:

• The leaf falls from the tree and remains on the ground

Latin does not need to say folium ... et folium manet, because the verb ending -t and the sentence structure already make it clear that the same leaf is still the subject.

Yes, but the nuance would be a little different.

• de arbore suggests down from or off the tree
• ex arbore suggests out of or from within the tree, though it can sometimes also mean simply from

For a leaf falling off a tree, de arbore is very natural, because the leaf is thought of as coming down from the tree.

Placing folium first makes the sentence start with the main topic: the leaf.

Latin often places:

• the subject early,
• important complements in the middle,
• and the verb later or at the end.

So this sentence has a very readable narrative shape:

• Folium — topic
• de arbore — source
• cadit — action
• et in terra manet — second action and result

This is a common and natural way to build a Latin sentence.