Puer quaerit utrum praepositio “cum” ablativum semper habeat necne, et magistra ridens dicit eam semper ablativum habere.

Because quaerit introduces an indirect question: the boy is asking whether something is true. In Latin, indirect questions normally use the subjunctive.

So:

• utrum ... necne = whether ... or not
• habeat is subjunctive because it belongs to that indirect question

The subject of habeat is praepositio, so the verb is singular.

It means whether ... or not.

This is a very common Latin way to introduce an indirect yes/no question:

• utrum = opens the question, roughly whether
• necne = or not

So utrum praepositio cum ablativum semper habeat necne means whether the preposition cum always takes the ablative or not.

Because the sentence is talking about the word itself as a grammatical item.

Latin often does this when discussing language:

• praepositio cum = the preposition cum

So cum is not being used here in its normal grammatical function; it is being mentioned as a word under discussion.

As a preposition, yes: cum takes the ablative.

Examples:

• cum amico
• cum puella
• cum magistro

A very important exception in appearance, but not really in grammar, is with personal pronouns:

• mecum
• tecum
• nobiscum
• vobiscum
• secum

These are still ablative forms.

But cum is not always a preposition. It can also be a conjunction meaning things like when, since, or although. In that use, it does not govern a case at all. That is why the sentence specifically says praepositio cum.

Because it is the object of habeat and habere.

Latin often says that a preposition has or takes a certain case. So:

• ablativum habere = to take the ablative

You can think of an understood noun such as casum:

• casum ablativum = the ablative case

So the accusative makes sense: it is the thing being had or taken.

Because after verbs of saying, Latin very often uses the accusative-and-infinitive construction.

So:

• dicit = she says
• eam ... habere = that it has/takes ...

This is the normal classical way to report a statement.

So magistra ... dicit eam semper ablativum habere literally means something like:

• the teacher says it always to-have the ablative

Natural English:

• the teacher says that it always takes the ablative

Eam refers back to praepositio.

Since praepositio is a feminine noun, the pronoun referring to it is feminine too:

• praepositio = feminine
• eam = it, referring to that feminine noun

It is accusative because, in the accusative-and-infinitive construction, the subject of the infinitive is put in the accusative.

So in eam ... habere, eam is not the direct object of dicit; it is the logical subject of habere.

Ridens is the present participle of rideo, meaning laughing or smiling.

It agrees with magistra and describes what she is doing while she speaks:

• magistra ridens = the teacher, laughing / the laughing teacher / the teacher with a smile

A natural English translation is often:

• the teacher, laughing, says ... or
• the teacher says with a laugh ...

Because present participles are third-declension adjectives, and their nominative singular masculine and feminine forms are the same.

So:

• masculine nominative singular: ridens
• feminine nominative singular: ridens

That is completely normal. It still agrees with magistra, even though it does not end in -a.

Because Latin word order is much freer than English word order.

The main structure is:

• Puer quaerit ...
• et magistra ridens dicit ...

Inside those, Latin places words where they fit naturally for emphasis and grouping rather than following a rigid English-style order.

Helpful chunks are:

• utrum praepositio cum ablativum semper habeat necne
• eam semper ablativum habere

So even if the order feels unusual, the grammar tells you how the pieces fit together.

Because the second half directly answers the first half.

The boy asks whether cum always takes the ablative, and the teacher says that it always does. Repeating semper keeps the wording parallel and clear.

So the sentence is neatly balanced:

• question: does it always take the ablative?
• answer: yes, it always takes the ablative