У брата в ящике всегда лежит отвёртка на случай ремонта.

Because у + genitive is a very common Russian pattern meaning something like:

• at someone's place
• with someone
• or, in many contexts, someone has

So у брата does not make brother the grammatical subject. Instead, it sets the scene: the screwdriver is with / at the brother's place, specifically in his drawer.

This is one of the main ways Russian expresses possession.

The preposition у requires the genitive.

So:

• брат = nominative
• брата = genitive

This is not because of the verb or because of possession alone; it is specifically because у governs the genitive.

You will see the same pattern in sentences like:

• У сестры есть машина
• У друга дома книги

By itself, брата does not tell you that clearly.

Russian has no articles, so it does not mark a vs the the way English does. Also, Russian often leaves out possessives like my when they are obvious from context.

So depending on context, у брата could mean:

• at my brother's place
• at the brother's place
• at a brother's place

In real usage, learners often see this translated as my brother's, because that is a very natural interpretation in many contexts.

Because в can take different cases depending on meaning:

• в + accusative = motion into something
• в + prepositional = location inside something

Here there is no movement. The screwdriver is already there, so Russian uses the prepositional case:

• ящик → в ящике

Compare:

• положить в ящик = to put into the drawer
• лежать в ящике = to lie in the drawer

The subject is отвёртка.

A learner can get confused because the sentence starts with у брата в ящике, but those are just location/possession phrases. The thing that actually lies there is the screwdriver.

That is why the verb is лежит in the singular: it agrees with отвёртка, not with брат or ящик.

Russian often prefers a position verb where English might simply use is.

лежит literally means lies or is lying. It suggests that the object is in a horizontal resting position. For a screwdriver in a drawer, that sounds very natural.

This gives the sentence a more concrete, physical feel than a neutral verb like находится.

Common position verbs include:

• лежать = to lie
• стоять = to stand
• сидеть = to sit
• висеть = to hang

Russian uses these much more often than English does.

Yes, but it would not sound exactly the same.

• У брата в ящике есть отвёртка
  This mainly says that such an item exists there / he has one there.

• У брата в ящике лежит отвёртка
  This sounds more natural if you want to describe where it is kept physically.

So есть is more about existence or possession, while лежит is more about actual location and position.

Because it is the subject of the sentence.

Even though it comes after the verb, it is still the thing performing the state described by the verb: the screwdriver lies in the drawer.

Russian word order is flexible, so the subject does not have to come first. Case endings tell you the role:

• отвёртка = nominative singular
• therefore it is the subject

This is a fixed and very useful pattern:

• на случай + genitive

It means:

• in case of ...
• for the case of ...
• more naturally in English, often in case ... is needed

So на случай ремонта means something like in case repairs are needed or for repair situations.

Russian often uses a noun phrase here where English might prefer a clause.

Because the expression на случай requires the genitive.

So:

• ремонт = nominative
• ремонта = genitive

You can think of на случай as a set phrase that works the same way in many examples:

• на случай дождя = in case of rain
• на случай пожара = in case of fire
• на случай поломки = in case of a breakdown

Quite flexible. Russian word order often changes to shift emphasis rather than basic meaning.

For example, these are all possible with different focus:

• У брата в ящике всегда лежит отвёртка
• В ящике у брата всегда лежит отвёртка
• Отвёртка всегда лежит у брата в ящике

The original version sounds natural because it starts with the setting and ends with the important noun отвёртка.

Very roughly:

• earlier in the sentence = background, known information
• later in the sentence = new or emphasized information

Yes, всегда can move, but the emphasis changes slightly.

In the original sentence, всегда sits before the verb and naturally modifies the whole situation: the screwdriver is always there.

Other placements are possible:

• У брата в ящике отвёртка всегда лежит
• Всегда у брата в ящике лежит отвёртка

These are grammatical, but they may sound more marked or stylistically different. The original placement is the most neutral and natural for everyday speech.

Yes: the ё matters.

It is pronounced with stress on that syllable: отвЁртка.

In printed Russian, ё is often replaced by е, so you may see отвертка. But the pronunciation is still отвёртка.

For learners, this matters because е and ё are not pronounced the same way. If you know the word already, it is best to remember it with ё.