يعزل الفني الحائط.

Arabic often uses verb–subject–object word order, especially in straightforward statements.

So:

• يعزل = the verb, he insulates / he isolates
• الفني = the subject, the technician
• الحائط = the object, the wall

So the sentence structure is:

• يعزل الفني الحائط
• literally: Insulates the technician the wall
• natural English: The technician insulates the wall

Arabic can also use subject–verb–object order:

• الفني يعزل الحائط

That is also correct, but يعزل الفني الحائط is a very normal MSA pattern.

Here is the breakdown:

• يعزل = verb
• الفني = subject / doer of the action
• الحائط = direct object / thing receiving the action

So:

• The technician does the action
• the wall receives the action

In grammatical terms:

• يعزل = present-tense verb
• الفني = subject in the nominative
• الحائط = direct object in the accusative

يعزل comes from the root ع-ز-ل.

Depending on context, it can mean things like:

• to isolate
• to separate
• to insulate

With الحائط (the wall), the intended meaning is often insulates the wall, especially in a construction or maintenance context.

So the exact English translation depends on the situation, but the grammar stays the same.

Because it has the definite article الـ at the beginning.

• فني = a technician / technical worker
• الفني = the technician

The same is true for الحائط:

• حائط = a wall
• الحائط = the wall

So both the subject and the object are definite here.

With full case endings, it would be pronounced:

• يَعْزِلُ الفَنِّيُّ الحَائِطَ

A rough transliteration is:

• yaʿzilu al-fanniyyu al-ḥāʾiṭa

Word by word:

• يَعْزِلُ = yaʿzilu
• الفَنِّيُّ = al-fanniyyu
• الحَائِطَ = al-ḥāʾiṭa

In normal unvocalized writing, those short vowels are usually not written.

Because everyday Arabic writing usually leaves out short vowels and case endings.

So you see:

• يعزل الفني الحائط

But the fully vocalized form is:

• يَعْزِلُ الفَنِّيُّ الحَائِطَ

Those final vowels show grammar:

• -ُ on يعزلُ = present-tense ending
• -ُ on الفنيُّ = nominative subject
• -َ on الحائطَ = accusative object

Learners often wonder how readers know the roles without vowels. Usually they know from:

• word order
• context
• grammar patterns

Because in Arabic grammar:

• the subject of a verbal sentence is normally nominative
• the direct object is normally accusative

So in:

• يَعْزِلُ الفَنِّيُّ الحَائِطَ

we get:

• الفنيُّ = nominative, because it is the one doing the action
• الحائطَ = accusative, because it is the thing being acted on

Even if the unvocalized spelling looks the same, the grammatical role is different.

Yes. الفني is a masculine singular noun, so the verb appears in masculine singular form:

• يعزل = he insulates / he isolates

If the subject were feminine singular, you would normally use:

• تعزل = she insulates

For example:

• تعزل الفنية الحائط = The female technician insulates the wall

So the verb form changes to match gender, and usually number as well.

Because this is not a sentence with the verb to be. It already has its own action verb:

• يعزل = insulates / isolates

So English The technician is insulating the wall or The technician insulates the wall is expressed in Arabic simply with the present-tense verb.

Arabic also often leaves out the present-tense is/am/are in nominal sentences, but here that issue does not arise because the sentence already contains a main verb.

Yes. That is also correct.

Compare:

• يعزل الفني الحائط = verb-first
• الفني يعزل الحائط = subject-first

Both can mean The technician insulates the wall.

The difference is mainly one of style, emphasis, or sentence flow:

• verb-first is very common in MSA
• subject-first can feel a bit more like explicitly introducing the technician as the topic

Both are worth recognizing.

Yes. فني is related to فن.

• فن originally means art
• فني can mean technical, artistic, or specialized, depending on context
• as a noun, فني often means technician or technical worker

In this sentence, الفني is being used as a noun meaning the technician, not just as an adjective.

No. Arabic has more than one word that can correspond to wall, depending on context.

Common words include:

• حائط
• جدار

Both can mean wall, though usage can vary by region and context.

In MSA, الحائط is completely valid here, and in this sentence it functions simply as the direct object of the verb.