يعرف مدى التلف.

• يعرف: a verb, he knows / he is aware of / it knows
• مدى: a noun meaning extent, degree, or range
• التلف: a noun meaning damage, spoilage, deterioration, or loss

So مدى التلف is a noun phrase meaning the extent of the damage.

يعرف is the imperfect (non-past) form of the verb عرف.

In this sentence, it is:

• 3rd person
• masculine
• singular

So by itself it usually means:

• he knows
• or sometimes it knows / it is aware of, depending on context

In simple translations, it is often rendered as a present tense in English.

The subject is not written separately. It is understood from the verb يعرف.

Arabic often leaves the subject pronoun unstated when the verb already shows it. Here the hidden subject is essentially:

• هو = he
• or sometimes it, if the context calls for that

So the sentence is complete even without an explicit subject.

Because this is a verbal sentence in Arabic.

Arabic very commonly starts sentences with the verb, especially in straightforward narration or description. So:

• يعرف = the verb comes first
• then comes what is known: مدى التلف

This is normal Arabic word order.

Here مدى means extent, degree, or how much in the sense of scope or amount.

It is often used in expressions like:

• مدى التأثير = the extent of the effect
• مدى النجاح = the extent of the success
• مدى التلف = the extent of the damage

So it is not the damage itself; it is how great the damage is.

Because Arabic usually expresses of by putting two nouns together in a structure called iḍāfa (the construct phrase).

So:

• مدى التلف literally looks like extent the-damage
• but it means the extent of the damage

English uses of. Arabic often does not need a separate word.

Because in an iḍāfa phrase, the first noun usually does not take الـ.

So:

• مدى التلف is correct
• المدى التلف would be wrong in standard Arabic

Even without الـ on مدى, the whole phrase is still definite because the second word التلف is definite. That is why the whole phrase means the extent of the damage, not just an extent of damage.

Grammatically:

• مدى is the direct object of يعرف, so it is accusative
• التلف is the second noun in the iḍāfa, so it is genitive

A more grammatical breakdown would be:

• يعرفُ: imperfect verb, indicative
• hidden subject: he / it
• مدى: direct object, accusative
• التلفِ: genitive because it is the second term of the construct phrase

One useful detail: مدى ends in alif maqṣūra (ى), so its case ending is not visibly written.

Because ت is a sun letter, the ل of الـ is not pronounced separately.

So التلف is pronounced roughly like:

• at-talaf when starting from it by itself

In full connected speech, the helping vowel of الـ can drop, so after مدى it may sound closer to:

• madā t-talaf(i)

A simple learner-friendly pronunciation for the whole sentence is:

• yaʿrifu madā at-talafi

Yes. The verb عرف can mean several related things, including:

• to know
• to recognize
• to be familiar with
• to identify

But with an abstract phrase like مدى التلف, the most natural sense is:

• knows
• is aware of
• can determine

So in this sentence, recognizes the extent of the damage is possible in some contexts, but knows the extent of the damage is usually the best fit.

Not always exactly. التلف often suggests:

• damage
• spoilage
• deterioration
• ruin
• loss through being damaged

It is especially common for things like:

• goods
• crops
• equipment
• materials

So it can overlap with English damage, but the exact nuance depends on context.

Yes, it can be a full sentence.

It has:

• a verb: يعرف
• an understood subject: he / it
• an object: مدى التلف

So even though it is short and context-dependent, it is grammatically complete. The main thing missing is just the wider context that tells you exactly who knows.