Il pediatra controlla l'arrossamento.

Pediatra can refer to either a male or a female pediatrician. The article tells you the gender here:

• il pediatra = the male pediatrician
• la pediatra = the female pediatrician

So in this sentence, il shows that the pediatrician is male.

Controlla is the third-person singular present tense of controllare.

Here it means something like:

• checks
• examines
• looks at

So Il pediatra controlla l'arrossamento means The pediatrician checks the redness.

Depending on context, controllare can also mean to control, but in medical or everyday contexts it often means to check.

Because arrossamento starts with a vowel, the masculine singular definite article il becomes l' before it.

So:

• il libro
• l'arrossamento

This is very common in Italian.

A few examples:

• l'amico
• l'esame
• l'occhio

Arrossamento is a noun meaning redness or reddening, especially in a medical or physical sense.

It comes from arrossare / arrossarsi, related to becoming red.

In medical language, arrossamento is often used for:

• skin redness
• irritation
• inflammation-related redness

So this sentence sounds very natural in a medical context.

Because not all masculine Italian nouns end in -o.

Pediatra is one of many nouns ending in -a that can still be masculine. This happens especially with words of Greek origin or certain professions.

Examples:

• il pediatra
• il problema
• il poeta
• il collega (can also be feminine with la collega)

So you cannot rely only on the final letter; you also need to learn the article.

Word order matters a lot for meaning.

In Il pediatra controlla l'arrossamento:

• Il pediatra = the subject
• controlla = the verb
• l'arrossamento = the object

So the pediatrician is doing the checking.

If you said L'arrossamento controlla il pediatra, it would literally mean The redness checks the pediatrician, which does not make sense in normal usage.

Italian can sometimes change word order for emphasis, but this basic subject + verb + object order is the clearest and most neutral.

Because Italian verb endings show the subject.

For controllare in the present tense:

• io controllo = I check
• tu controlli = you check
• lui/lei controlla = he/she checks

So controlla matches he/she.

Since the subject is il pediatra, the meaning is the pediatrician checks.

A simple pronunciation guide is:

lar-ros-sa-MEN-to

A few points:

• l' joins directly to the next word: l'arrossamento
• the double rr and double ss are pronounced more strongly than single consonants
• the stress falls on -men-

A rough English-friendly approximation is:

lah-rross-sah-MEN-to

Yes, the Italian present tense can cover several English present meanings, depending on context:

• checks
• is checking
• sometimes even a habitual sense like checks regularly

So this sentence could mean:

• The pediatrician checks the redness
• The pediatrician is checking the redness

Usually the context tells you which one sounds best in English.

Yes. The singular is:

• l'arrossamento = the redness

The plural is:

• gli arrossamenti = the reddenings / the areas of redness / the redness symptoms

In medical language, the plural can be used when talking about multiple red areas or episodes of redness.

Actually, both nouns do have the in Italian:

• Il pediatra = The pediatrician
• l'arrossamento = the redness

Italian uses definite articles very frequently, often even more often than English. In this sentence, both nouns need the article.

Yes. That would also be natural.

Some nearby verbs are:

• controllare = to check
• esaminare = to examine
• osservare = to observe
• guardare = to look at

Controlla is a very normal, everyday choice here.
Esamina sounds a bit more specifically like a medical examination.

Here is the breakdown:

• Il — definite article, masculine singular, the
• pediatra — noun, pediatrician
• controlla — verb, third-person singular present of controllare
• l' — shortened definite article before a vowel
• arrossamento — noun, redness

So the structure is:

article + noun + verb + article + noun