Magister non tantum exemplum bonum ostendit, sed etiam rationem clare explicat.

This is a very common Latin pairing. It means not only ... but also ...

In this sentence:

• non tantum exemplum bonum ostendit = he shows not only a good example
• sed etiam rationem clare explicat = but also explains the reason clearly

So Latin is linking two ideas:

1. the teacher shows a good example
2. the teacher also explains the reason clearly

A learner should remember this as a set phrase:

• non tantum = not only
• sed etiam = but also

You may also see a very similar version in Latin: non solum ... sed etiam ...

Magister is in the nominative singular, which is the case normally used for the subject of the sentence.

Here, magister is the person doing both actions:

• ostendit = shows
• explicat = explains

So magister is the subject of both verbs.

Its dictionary form is:

• magister, magistri = teacher

Because it is singular, the verbs are also singular.

They are both direct objects, but they belong to different declensions, so their accusative singular forms look different.

• exemplum is a 2nd-declension neuter noun

  • nominative singular: exemplum
  • accusative singular: exemplum
  • For many neuter nouns, nominative and accusative are the same.

• ratio is a 3rd-declension feminine noun

  • nominative singular: ratio
  • accusative singular: rationem

So:

• exemplum bonum ostendit = he shows a good example
• rationem clare explicat = he explains the reason clearly

Even though both are direct objects, their endings differ because their noun types differ.

Because bonum is describing exemplum, and adjectives in Latin must agree with the nouns they describe in:

• gender
• number
• case

Exemplum is:

• neuter
• singular
• accusative

So the adjective must also be:

• neuter
• singular
• accusative

That gives bonum.

So:

• exemplum bonum = a good example

If the noun were masculine nominative singular, then bonus might be correct, but not here.

In Latin, adjectives can come before or after the noun much more freely than in English.

So both of these are grammatically possible:

• bonum exemplum
• exemplum bonum

Both mean good example.

Latin word order is more flexible because the endings show the grammar. Placement often depends on style, emphasis, or rhythm rather than strict rules like in English.

A beginner should not assume that adjective position changes the basic meaning here. In this sentence, exemplum bonum simply means a good example.

Both are present tense, 3rd person singular, active voice.

• ostendit = he/she shows
• explicat = he/she explains

Because the subject is magister, we understand them as:

• the teacher shows
• the teacher explains

The endings help you identify this:

• -it in ostendit
• -at in explicat

These come from different conjugations, but both are present-tense singular forms here.

In some contexts, yes: ostendit can sometimes be either he shows or he showed, because certain Latin verb forms can look identical in the present and perfect systems for some verbs.

However, in a straightforward sentence like this, especially in beginner material, ostendit will normally be understood as present: he shows.

Why?

Because:

• it is paired with explicat, which is clearly present
• the sentence expresses a general habit or characteristic action of a teacher
• there is no context suggesting past time

So here the natural reading is definitely:

• the teacher shows
• the teacher explains

Because clare is an adverb, and it modifies the verb explicat.

It tells us how the teacher explains:

• clare explicat = explains clearly

An adjective would describe a noun, but here we need a word that describes the action of explaining.

Compare:

• clara ratio = a clear reason
  Here clara is an adjective describing ratio.

• rationem clare explicat = he explains the reason clearly
  Here clare is an adverb describing explicat.

This is similar to English:

• clear = adjective
• clearly = adverb

Classical Latin does not have definite or indefinite articles like English the and a/an.

So a noun like magister can mean:

• the teacher
• a teacher

And exemplum bonum can mean:

• a good example
• the good example

The exact choice in English depends on context.

In this sentence, English most naturally uses the teacher because it sounds like a general statement about what a teacher does:

• The teacher not only shows a good example, but also clearly explains the reason.

So learners should remember: Latin often leaves article meaning to context.

Latin has much freer word order than English because the endings tell you what each word is doing.

English depends heavily on position:

• The teacher explains the reason

If you rearrange that too much in English, it becomes confusing.

Latin is different. In this sentence:

• Magister is clearly the subject
• exemplum and rationem are objects
• bonum matches exemplum
• clare modifies explicat

Because the endings already show the relationships, Latin can arrange the sentence for emphasis and style.

This sentence is quite natural Latin:

• subject first: Magister
• first idea: non tantum exemplum bonum ostendit
• contrasting second idea: sed etiam rationem clare explicat

So the word order is not random, but it is much less rigid than English.

Yes, ratio is a very flexible Latin noun. Depending on context, it can mean things like:

• reason
• method
• plan
• system
• account
• calculation

Here, rationem clare explicat most naturally means explains the reason clearly or possibly explains the reasoning clearly.

That is a good example of how Latin words often cover a wider range of meanings than a single English word. The context tells you which sense fits best.

Not always in every Latin sentence, but here it functions together as part of the correlative expression non tantum ... sed etiam ...

So it is best understood as a unit:

• sed etiam = but also

Latin can sometimes separate related words more than English does, but for a learner, the safest approach is to recognize the whole pattern as one structure.

When you see:

• non tantum
• later followed by sed etiam

you should immediately think:

• not only ... but also ...

Because one subject can govern multiple verbs in Latin, just as in English.

Here, magister is the subject of both:

• ostendit
• explicat

Latin does not need to repeat magister before the second verb.

So the structure is essentially:

• The teacher not only shows a good example, but also explains the reason clearly.

This is very normal. If Latin repeated the subject, it would usually add extra emphasis or mark a change in structure.