الشرطي يساعد صديقي.

A careful pronunciation is ash-shurṭī yusāʿidu ṣadīqī.

A more fully grammatical reading with case endings is ash-shurṭiyyu yusāʿidu ṣadīqī.

A few useful notes:

• الـ is written in الشرطي, but because ش is a sun letter, al- is pronounced ash-.
• يساعد is pronounced yusāʿidu.
• صديقي is pronounced ṣadīqī.

No. These are two different things.

• In صديقي, the final ي really is the possessive suffix -ī, meaning my. So صديق = friend, and صديقي = my friend.
• In الشرطي, the final ي is part of the word itself. It does not mean my.

So:

• الشرطي = the police officer
• صديقي = my friend

Even though both words end in ي in writing, they are not functioning the same way.

Because both nouns are definite, but they become definite in different ways.

• الشرطي is definite because it has the definite article الـ, so it means the police officer.
• صديقي is definite because it has a possessive suffix: my friend. In Arabic, a noun with my/your/his/her attached is already definite, so you do not add الـ.

So Arabic does not say something like الصديقي for my friend.

It is built like this:

• صديق = friend
• ـي = my

So:

• صديق + ي = صديقي
• literally: friend + my

This is very common in Arabic. Instead of using a separate word for my, Arabic often adds a suffix directly to the noun.

Other examples:

• كتابي = my book
• بيتي = my house
• أخي = my brother

يساعد is a present/imperfect-tense verb, and here it means he helps, he is helping, or sometimes he does help, depending on context.

It tells you several things at once:

• يـ at the beginning marks 3rd person masculine singular in the imperfect
• so the verb by itself means he helps
• its dictionary/past form is ساعد = he helped
• the verb is from Form III, which often has a long ā sound: ساعَدَ / يُساعِدُ

So يساعد already contains the idea of he.

Because the verb already includes that information.

In Arabic, يساعد already means he helps. So you do not need a separate pronoun like هو unless you want emphasis or contrast.

That means:

• يساعد = he helps
• هو يساعد = he is helping / he helps, but with extra emphasis on he

Since the sentence already has the subject noun الشرطي, adding هو would usually be unnecessary.

In this sentence:

• الشرطي = the subject
• يساعد = the verb
• صديقي = the object

So the pattern here is:

• Subject + Verb + Object
• الشرطي يساعد صديقي
• The police officer helps my friend

This word order is perfectly normal in Arabic.

Yes. Arabic often allows both:

• الشرطي يساعد صديقي
• يساعد الشرطي صديقي

Both can mean The police officer helps my friend.

The first is SVO:

• Subject–Verb–Object

The second is VSO:

• Verb–Subject–Object

Both are common in Modern Standard Arabic, though they can sound slightly different in style or emphasis depending on context.

Because the subject الشرطي is masculine singular.

Arabic verbs agree with the subject in gender and number, though the exact agreement pattern can depend on word order. In this sentence, the subject is one male police officer, so the verb is 3rd person masculine singular:

• يساعد = he helps

If the subject were feminine singular, you would use:

• تساعد = she helps

For example:

• الشرطية تساعد صديقي = The female police officer helps my friend

In normal Arabic writing, short vowels and most case endings are usually not written.

So you usually see:

• الشرطي يساعد صديقي

But a fully vocalized version would look more like:

• الشُّرْطِيُّ يُسَاعِدُ صَدِيقِي

A few important points:

• الشرطي is the subject, so it is nominative: -u in full grammar
• يساعد is in the indicative here: also -u
• صديقي is the object, but with the my suffix, its form does not visibly change here the way a simple noun might

So the grammar is still there, but everyday writing usually leaves those endings unwritten.