La contestazione riguarda l'infrazione.

Because infrazione is a feminine singular noun that begins with a vowel, and in Italian la becomes l' before a vowel for smoother pronunciation.

• la contestazione
• l'infrazione

This is very common:

• la amica → l'amica
• lo articolo → l'articolo

So l'infrazione is just the normal shortened form of la infrazione.

Riguarda is the third-person singular present tense of riguardare.

So it means:

• (he/she/it) concerns
• (he/she/it) regards
• (he/she/it) is about

In this sentence, the subject is la contestazione, which is singular, so the verb must also be singular:

• La contestazione riguarda...

If the subject were plural, the verb would change:

• Le contestazioni riguardano l'infrazione.

Because riguardare is normally a direct transitive verb in Italian. It takes a direct object without a preposition.

So Italian says:

• riguardare qualcosa

not

• riguardare di qualcosa
• riguardare a qualcosa

That can feel unusual for an English speaker because English often uses different patterns depending on the verb, but here the structure is straightforward:

• La contestazione = subject
• riguarda = verb
• l'infrazione = direct object

Italian uses definite articles more often than English does. In this sentence, both nouns are specific:

• la contestazione
• l'infrazione

English might sometimes omit an article in similar contexts, but Italian usually keeps it when talking about a specific act, event, or legal matter.

So even if English style might vary, Italian naturally says:

• La contestazione riguarda l'infrazione.

not usually just

• Contestazione riguarda infrazione.

That would sound incomplete or unnatural in standard Italian.

Yes, they are related, but you should be careful because the usage is not always identical.

In Italian, contestazione can mean things like:

• a dispute
• an objection
• a challenge
• in legal/administrative contexts, a formal charge, citation, or notice of violation

So although it resembles English contestation, the Italian word is often more common and practical in official language than the English cognate is in everyday English.

This is a good example of a word that is partly transparent for English speakers, but still needs attention in context.

Because both nouns end in -zione, and nouns ending in -zione are almost always feminine in Italian.

So:

• la contestazione
• l'infrazione
• la situazione
• la decisione is a little different in ending, but also feminine

This is a very useful pattern to remember: -zione = usually feminine

Yes, Italian word order is somewhat flexible, but this sentence in the given order is the most neutral and natural.

Standard order:

• La contestazione riguarda l'infrazione.

This is simply: subject + verb + object

You could change the order in special contexts for emphasis, but then the sentence may sound more marked, literary, or context-dependent. For a learner, the version you have is the safest and most natural one to use.

Also, if you switched the two nouns, the meaning would change:

• L'infrazione riguarda la contestazione = The violation concerns the objection/charge

That is a completely different sentence.

They are similar, and in many contexts both can refer to breaking a rule, but there is often a nuance.

• infrazione often suggests a breach of a rule or regulation, especially in legal, administrative, or traffic contexts.
• violazione can sound broader and can refer to a violation of laws, rights, rules, privacy, etc.

So infrazione is often a very good choice for things like:

• traffic offenses
• rule-breaking
• administrative violations

While violazione can be wider in meaning.

In many official contexts, though, the exact choice depends on legal wording.

A rough pronunciation guide is:

La contestazione riguarda l'infrazione
lah kon-teh-sta-TSYO-ne ree-GWAR-da leen-fra-TSYO-ne

A few useful points:

• zione sounds roughly like tsyoh-neh
• giu in riguarda sounds like gw: ree-GWAR-da
• l'infrazione links smoothly after the apostrophe, almost like one unit

If you want to sound natural, keep the rhythm flowing and stress:

• contestaZIÓne
• riguarDA
• infraZIÓne

Yes, in some contexts riguardare can mean to concern, to relate to, or to regard, and in older or more literary usage it can also have senses connected with looking at or examining. But in modern everyday Italian, in a sentence like this, the meaning is clearly:

• to concern
• to be about
• to relate to

So here riguarda should be understood as a verb of relation, not literal sight.

Yes, it sounds fairly formal and especially natural in administrative, bureaucratic, or legal Italian.

Words like:

• contestazione
• infrazione

are common in official contexts such as:

• fines
• police reports
• administrative notices
• legal documents

So a learner should recognize that this sentence has a somewhat official register, even though the grammar itself is completely standard.