في إبريق السقي ماء.

Because Arabic often uses a prepositional phrase first to express location or existence.

So في إبريق السقي ماءٌ literally has the structure:

• في إبريق السقي = in the watering jug / in the watering can
• ماءٌ = water

This is a very common Arabic pattern for saying something like there is water in the watering jug.

Grammatically, the location phrase comes first, and the noun being talked about comes after it.

In Arabic, the present tense often does not need a verb like is / are.

This is a nominal sentence. Arabic can simply put the parts of the sentence together and the meaning is or there is is understood from context.

So:

• في البيت رجلٌ = There is a man in the house
• في إبريق السقي ماءٌ = There is water in the watering jug

If you want, you can also say يوجد ماءٌ في إبريق السقي, which also means There is water in the watering jug, but the sentence without يوجد is very normal and natural in Arabic.

Because the sentence is presenting what exists in that place.

Arabic often uses this order:

• location first
• thing existing there second

So the sentence is structured like:

• In the watering jug ...
• ... there is water

Putting ماءٌ at the end makes it the thing being introduced.

If you moved it to the front, the sentence would not sound the same. Compare:

• في إبريق السقي ماءٌ = There is water in the watering jug
• الماءُ في إبريق السقي = The water is in the watering jug

The second one talks about the water as something already known, while the first one introduces water as something present in that location.

Because in this kind of existential sentence, Arabic usually uses an indefinite noun.

So:

• ماءٌ = water / some water
• الماءُ = the water

With في إبريق السقي ماءٌ, the meaning is like there is water in the watering jug.

If you said في إبريق السقي الماءُ, that would be much less natural in this structure, because existential sentences usually introduce something indefinite.

If you want to talk about a specific known water, you would more naturally say:

• الماءُ في إبريق السقي = The water is in the watering jug

So the choice between ماء and الماء affects the meaning and sentence type.

Because إبريق comes after the preposition في, and nouns after prepositions are normally in the genitive case in Arabic.

So:

• في = in
• في إبريقِ = in a jug / in the jug

That is why إبريق takes the genitive ending.

In fully vowelled form, the phrase is:

• في إبريقِ السقيِ ماءٌ

Here:

• إبريقِ is genitive because it follows في
• السقيِ is also genitive because it is the second part of an iḍāfa construction
• ماءٌ is nominative because it is the main noun being asserted in the sentence

This is an iḍāfa construction, often called a genitive construction or noun + noun possession/type construction.

It works like this:

• إبريق = jug, pitcher
• السقي = watering, irrigation

Together, إبريق السقي means something like:

• the watering jug
• the watering pitcher
• the watering can

So the second noun explains the type or purpose of the first noun.

This is very common in Arabic. For example:

• باب البيت = the door of the house
• كوب الماء = the cup of water
• حقيبة المدرسة = the school bag

In إبريق السقي, the first noun usually does not take الـ, while the second noun can.

Because in an iḍāfa, the second noun can be definite, and when it is definite, the whole phrase becomes definite.

So:

• إبريقُ سقيٍ would mean something like a watering jug
• إبريقُ السقيِ means the watering jug or the jug for watering

The الـ is attached only to the second noun, not the first.

That is normal in Arabic iḍāfa phrases. For example:

• كتابُ الطالبِ = the student's book
• not الكتابُ الطالبِ in iḍāfa form

So إبريق السقي is built in the same way.

A common analysis is:

• في إبريق السقي = a prepositional phrase functioning as a fronted predicate
• ماءٌ = a delayed subject or delayed topic

In traditional Arabic grammar terms, this is often described as:

• شبه جملة as خبر مقدّم
• ماءٌ as مبتدأ مؤخّر

You do not need to master those labels right away, but the important idea is this:

• the sentence first gives the place
• then it names what is there

That is why the whole sentence means there is water in the watering jug.

In fully vowelled Classical/MSA style, you would usually write:

في إبريقِ السقيِ ماءٌ

The endings are:

• في = preposition
• إبريقِ = genitive because it follows في
• السقيِ = genitive because it is the second noun in the iḍāfa
• ماءٌ = nominative, with tanwīn, because it is indefinite and functions as the main noun in the sentence

In normal reading or speaking, especially in pause, many final short vowels may not be pronounced clearly, but the grammatical pattern is still there.

Yes. That is also correct and very common.

Compare:

• في إبريق السقي ماءٌ
• يوجد ماءٌ في إبريق السقي

Both can mean There is water in the watering jug.

The first is a simple nominal structure and is very common in Arabic. The second uses يوجد = there exists / there is, which may feel more straightforward to an English speaker because it contains an explicit verb.

Both are useful to know.

It is more naturally understood as there is water in the watering jug.

That is because:

1. the sentence begins with a location phrase
2. the noun ماءٌ is indefinite

That combination strongly suggests an existential meaning: something is present somewhere.

If Arabic wanted to say the water is in the watering jug, it would more naturally use a definite noun at the start:

• الماءُ في إبريق السقي

So the difference is not just word order; it is also about whether the noun is definite or indefinite.

Not necessarily. Arabic has several ways to express similar meanings depending on context and vocabulary choice.

For example, a speaker might use another word for a container depending on whether they mean:

• a jug
• a pitcher
• a watering can

But grammatically, the pattern in your sentence is very useful and common:

• في + place + indefinite noun

That pattern is worth learning because it appears all the time in MSA.

For example:

• في الغرفةِ كرسيٌّ = There is a chair in the room
• على الطاولةِ كتابٌ = There is a book on the table
• في الزجاجةِ ماءٌ = There is water in the bottle

So even if the vocabulary item changes, the sentence structure remains very important.