Si non es certus, magistram ipsam interroga; ipsa enim optimum consilium saepe dat.

Because magistram is the direct object of interroga.

• magistra = the teacher as a subject
• magistram = the teacher as an object

Latin shows a noun’s job in the sentence by its case ending. Here, interroga means ask, and the person being asked is put in the accusative case, so magistra becomes magistram.

ipsam means herself and adds emphasis.

So magistram ipsam interroga means something like:

• ask the teacher herself
• ask the teacher in person
• ask the teacher directly

It is not a separate pronoun standing alone here; it agrees with magistram:

• feminine
• singular
• accusative

That is why it is ipsam, not ipse or ipsa.

In the second clause, ipsa again adds emphasis, but now it is nominative because it refers to the subject:

• ipsa enim optimum consilium saepe dat = for she herself often gives the best advice

So the two forms are different because they do different grammatical jobs:

• ipsam modifies the object magistram
• ipsa is the subject of dat

Latin often repeats this kind of emphatic word where English might not.

Yes. certus agrees with the understood subject you (tu).

Since the sentence says es certus (you are sure/certain), the adjective is masculine singular. If the speaker were addressing a woman, Latin would normally say:

Si non es certa ...

So:

• certus = said to a man
• certa = said to a woman

Latin adjectives must agree with the person or thing they describe.

Because Latin, like English, often uses an adjective after to be.

Compare English:

• you are certain
• you are sure

Latin does the same:

• es certus = you are certain / sure

So certus is a predicate adjective, not an adverb.

Interroga is the singular present imperative of interrogare.

It means ask! or question!, said to one person.

So:

• interroga = ask! (to one person)
• interrogate in English is related, but in Latin interrogare is the ordinary verb for asking someone

If the command were said to more than one person, it would be:

• interrogate = ask! (to several people)

Because in Latin, the person you ask is commonly a direct object.

So Latin says:

• magistram interroga = ask the teacher

not something literally like ask to the teacher.

This is normal Latin usage. The person asked goes in the accusative.

Because enim is a postpositive word. That means it usually comes in second position, not first.

So Latin prefers:

• ipsa enim ...

rather than:

• enim ipsa ...

Here enim means for, indeed, or you see, depending on context. It gives the reason for the command in the first clause.

Literally, it means the best advice or the best counsel.

• optimum = best (accusative neuter singular)
• consilium = advice, plan, counsel, decision, depending on context

Here consilium is neuter singular, so optimum is also neuter singular to agree with it.

A native English speaker may expect advice to be an uncountable word, but Latin can use consilium in the singular very naturally for advice/counsel.

Latin word order is much more flexible than English word order because the endings show each word’s role.

This sentence could be arranged in other ways and still mean basically the same thing. But the given order helps with emphasis:

• magistram ipsam puts stress on the teacher herself
• ipsa enim again highlights she herself
• saepe dat leaves the verb to the end, which is very common in Latin

So the word order is not random; it helps foreground the important ideas.

Yes, grammatically it could.

For example:

Si non es certus, magistram interroga; enim optimum consilium saepe dat.

But that would lose an important emphasis, and the second clause would also need a clearer subject. The original sentence is stronger because it stresses that the teacher herself is the one to ask, and she herself is the one who gives the best advice.

So the repeated ipse, ipsa, ipsum adds force, not just information.

Yes, very normal.

It is a simple si clause:

• si = if
• non = not
• es = you are
• certus = sure/certain

So the structure is straightforward:

• If you are not sure, ask ...

This is an ordinary present-time conditional in Latin.