يذبل النبات المنزلي.

A careful full reading is:

yadhbulu an-nabātu al-manziliyyu

A few helpful pronunciation points:

• يذبل = yadhbulu
  • ذ sounds like th in this
• النبات is pronounced an-nabāt(u), not al-nabāt(u)
  • That is because ن is a sun letter, so the l of الـ assimilates
• المنزلي is pronounced al-manziliyy(u)
  • م is a moon letter, so the l of الـ is pronounced normally

In everyday pausal reading, the final short vowels are often not heard clearly.

Yes. يذبل is in the imperfect verb form, which commonly corresponds to the present in English.

Depending on context, it can mean things like:

• is withering
• withers
• is wilting

So it can describe:

• something happening now
• a general tendency
• a repeated situation

Because the subject here is النبات, which is grammatically masculine singular.

In the present tense:

• يـ is used for he / it (masculine)
• تـ is used for she / it (feminine)

So:

• يذبل النبات = the plant withers
• تذبل النبتة = the plant withers

If you changed the noun to the feminine word نبتة, then the verb would usually be تذبل.

Because this is a very normal Arabic verbal sentence pattern:

verb + subject + adjective

So:

• يذبل = withers
• النبات = the plant
• المنزلي = domestic / indoor / home

Arabic also allows:

النبات المنزلي يذبل

That version is also correct, but it feels more like a topic-first structure: The houseplant is withering. The original sentence is the more straightforward verbal style.

It is an adjective phrase, not an iḍāfa.

Here:

• النبات = the noun
• المنزلي = the adjective describing it

You can tell it is an adjective because المنزلي agrees with النبات in:

• definiteness
• gender
• number
• case

So this is basically:

the plant + the domestic/indoor

In natural English, that becomes the houseplant or the indoor plant.

Because Arabic adjectives must agree with the nouns they describe in definiteness.

So if the noun is definite:

• النبات = the plant

then the adjective must also be definite:

• المنزلي = the domestic/indoor

That is why you get:

النبات المنزلي

If the phrase were indefinite, it would be:

نبات منزلي

which means an indoor plant or a houseplant.

المنزلي comes from منزل meaning house or home.

The ending -ي is a very common Arabic way to make an adjective related to something. This is often called the nisba ending.

So:

• منزل = home, house
• منزلي = domestic, home-related, household, indoor

In this sentence, المنزلي means something like:

• domestic
• household
• indoor

So النبات المنزلي is the natural Arabic way to express houseplant.

Yes, absolutely.

That sentence is also very natural:

تذبل النبتة المنزلية

It uses:

• نبتة = a plant, a plant specimen, a single plant
• المنزلية = feminine adjective
• تذبل = feminine singular verb

This version may feel more clearly like a single plant.

By contrast, النبات can sometimes be a broader word meaning:

• plant life
• vegetation
• plants in general

But in context, it can also refer to a plant such as a houseplant.

If fully vowelled, the sentence is:

يَذْبُلُ النَّبَاتُ الْمَنْزِلِيُّ

Here is why:

• يَذْبُلُ: present tense indicative, so it ends in -u
• النَّبَاتُ: the subject of the verb, so it is nominative
• الْمَنْزِلِيُّ: adjective describing the subject, so it also takes the nominative

In normal Arabic writing, these short vowels are usually omitted, so learners often see:

يذبل النبات المنزلي

without the endings written.

The root is ذ ب ل.

This root is connected with the idea of:

• withering
• wilting
• drying up

The basic past-tense form is:

ذَبُلَ = it withered

The present form is:

يَذْبُلُ = it withers / is withering

A related verbal noun you may see is:

ذُبول = withering, wilting

Learning the root helps you recognize related vocabulary more easily.