ينصب صديقي الخيمة بأوتاد الخيمة قرب البحيرة.

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

So:

• ينصب = he pitches / he sets up
• صديقي = my friend
• الخيمة = the tent

That gives:

• ينصب صديقي الخيمة = My friend pitches the tent

You could also say:

• صديقي ينصب الخيمة

That is also correct, but it puts a little more focus on my friend as the topic.

Here ينصب means he sets up, he erects, or he pitches.

In this sentence, the natural English meaning is pitches or sets up, because the object is الخيمة = the tent.

So:

• ينصب الخيمة = he pitches the tent

This verb can have other meanings in other contexts, so learners should not assume it always means only one thing. Here the tent makes the meaning clear.

صديقي is made of:

• صديق = friend
• ـي = my

So:

• صديقي = my friend

The ـي is a possessive suffix attached directly to the noun.

This is a very common Arabic pattern:

• كتابي = my book
• بيتي = my house
• صديقي = my friend

Because it is the thing being set up.

In ينصب صديقي الخيمة:

• ينصب = pitches / sets up
• صديقي = the doer of the action
• الخيمة = the thing affected by the action

So الخيمة is the direct object.

If the sentence were fully vowelled, it would be:

• الخيمةَ

That final fatḥa shows the accusative case, which is the usual case for a direct object.

بأوتاد الخيمة means with the tent pegs or more literally with the pegs of the tent.

It has two parts:

• بـ = with / by means of
• أوتاد الخيمة = the pegs of the tent

And inside that phrase:

• أوتاد = pegs
• الخيمة = the tent

So the structure is:

• بـ + أوتاد الخيمة
• with + pegs of the tent

This whole phrase tells you the instrument or means used to pitch the tent.

Because this is an iḍāfa structure, often called a genitive construction.

In an iḍāfa:

• the first noun usually does not take ال
• the second noun tells whose or what kind

So:

• أوتاد الخيمة = the tent's pegs / the pegs of the tent

Even though أوتاد does not have ال, the whole phrase is still definite because الخيمة is definite.

Compare:

• أوتاد خيمة = pegs of a tent
• أوتاد الخيمة = pegs of the tent

Yes, Arabic could use a pronoun instead.

The sentence repeats الخيمة for clarity:

• ينصب صديقي الخيمة بأوتاد الخيمة

That is perfectly grammatical and very clear.

But Arabic could also say:

• ينصب صديقي الخيمة بأوتادها

Here:

• ها = its
• أوتادها = its pegs

So بأوتادها means with its pegs.

Learners often see both styles. Repeating the noun can sound clearer, especially in teaching examples.

The singular is:

• وَتَد = peg, stake

The plural is:

• أوتاد = pegs, stakes

This is a broken plural, which means the plural is formed by changing the internal pattern of the word, not just adding an ending.

So:

• وتد → أوتاد

Broken plurals are extremely common in Arabic, so this is a useful pattern to get used to.

قرب البحيرة means near the lake.

• قرب = near / nearby
• البحيرة = the lake

Grammatically, قرب is often treated as a noun of place / ظرف مكان used adverbially. The noun after it comes in the genitive:

• قربَ البحيرةِ

So even though English just says near the lake, Arabic is using a structure that is slightly more noun-like.

For a learner, the easiest practical understanding is:

• قرب البحيرة = near the lake

A fully vowelled version would be:

يَنْصِبُ صَدِيقِي الْخَيْمَةَ بِأَوْتَادِ الْخَيْمَةِ قُرْبَ الْبُحَيْرَةِ

This shows several useful case/endings:

• يَنْصِبُ = present tense verb
• صَدِيقِي = my friend
• الْخَيْمَةَ = the tent, direct object in the accusative
• بِأَوْتَادِ = with pegs, after بـ so genitive
• الْخَيْمَةِ = of the tent, second part of iḍāfa, genitive
• قُرْبَ = near, used adverbially
• الْبُحَيْرَةِ = the lake, genitive after قرب

This is a good sentence for seeing how Arabic links verbs, possession, and location together.