Odaégettem a fokhagymát, ami nem jó.

The base verb is égetni, meaning to burn.

The prefix oda- adds the idea of something being burned onto something or getting scorched/stuck while cooking. In kitchen context, odaégetni often means to scorch accidentally, especially in a pan or pot.

So odaégettem a fokhagymát is more like:

• I scorched the garlic
• I burned the garlic
• I let the garlic burn

rather than just a very general I burned it.

In Hungarian, verbal prefixes are normally written together with the verb when the sentence is in a neutral affirmative form.

So:

• odaégettem = prefix + verb together

But if something like negation or strong focus comes before the verb, the prefix usually separates:

• Nem égettem oda a fokhagymát. = I didn’t burn the garlic.
• A fokhagymát égettem oda. = It was the garlic that I burned.

So in your sentence, the neutral order makes odaégettem one word.

It is:

• past tense
• first person singular

So it means I burned or, depending on context, I have burned.

The ending -tem shows a past-tense I form. Hungarian usually does not need the subject pronoun én because the verb form already shows who the subject is.

Usually, yes.

In cooking, odaégetni often suggests that you accidentally let something burn or scorch. It sounds very natural for kitchen mistakes.

Compare a few related verbs:

• megégetni = to burn something / to cause a burn
• elégetni = to burn something up completely
• odaégetni = to scorch something, often onto the pan/pot

So here the feeling is very much I accidentally overdid the garlic.

Because fokhagymát is the direct object of the verb, so it takes the accusative ending -t.

• base form: fokhagyma = garlic
• object form: fokhagymát = garlic as the thing being acted on

Also notice that the final -a becomes long -á before the ending:

• fokhagyma → fokhagymát

This vowel lengthening is very common in Hungarian.

Because the sentence is talking about a specific garlic in the situation — for example, the garlic you were cooking.

So a fokhagymát means:

• the garlic
• the garlic in question
• the garlic I was working with

Hungarian uses the definite article very naturally in cases like this, especially when the thing is identifiable from context.

Here ami most naturally refers to the whole previous situation:

• Odaégettem a fokhagymát, ami nem jó.
• I burned the garlic, which is not good.

So ami nem jó means which is not good, where which refers to the fact that the garlic got burned.

It is not mainly describing the garlic itself as a noun; it is commenting on the event or situation.

In everyday Hungarian, ami is very commonly used as a relative pronoun.

A useful rough guide is:

• amely = often more formal, especially when referring back to a specific noun
• ami = very common in speech, and also natural when referring to a whole idea or previous clause

Since this sentence comments on the whole situation (burning the garlic), ami is especially natural here.

Because Hungarian normally leaves out van (is) in the third person singular present tense when the predicate is a noun or adjective.

So:

• jó = good
• nem jó = is not good

Hungarian does not need an extra word for is here.

Compare:

• Ez jó. = This is good.
• Ez nem jó. = This is not good.

But in other persons or tenses, forms of van do appear.

Because ami nem jó is a relative clause, and Hungarian separates relative clauses with a comma.

So the comma marks the added comment:

• Odaégettem a fokhagymát, ami nem jó.

It works much like English which is not good.

This is a fairly neutral word order.

• Odaégettem comes first as the verb with its prefix
• a fokhagymát follows as the object

This sounds like a straightforward statement of what happened.

If you wanted emphasis, the order could change. For example:

• A fokhagymát égettem oda. = It was the garlic that I burned.
• Nem égettem oda a fokhagymát. = I didn’t burn the garlic.

So the original sentence is the simple, natural way to say it.