В предбаннике лежат полотенца.

Because в means in here, and when Russian uses в to show location, the following noun normally goes into the prepositional case.

• предбанник = the dressing room / anteroom before a bathhouse
• в предбаннике = in the dressing room

So this is a standard location pattern:

• в доме = in the house
• в комнате = in the room
• в предбаннике = in the pre-bath room / changing area

Because предбанник is in the prepositional singular.

Its basic form is:

• предбанник — nominative singular

After в for location, it becomes:

• в предбаннике

This is a common pattern for many masculine nouns ending in a consonant:

• стол → на столе
• музей → в музее
• предбанник → в предбаннике

So the ending changes because the noun is no longer in its dictionary form.

Предбанник is a very Russian cultural word. It literally refers to the room before the баня (bathhouse/sauna area). It can function like a changing room, waiting room, or entry area before the steam room.

So depending on context, it might be translated as:

• anteroom
• changing room
• dressing room
• entry room before the bathhouse

A direct one-word English equivalent often does not exist, so the best translation depends on context.

Russian usually does not use есть in the same way English uses there is/there are for ordinary present-tense descriptions of location.

Instead, Russian often uses a verb that describes the object's position:

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

Since towels usually lie flat somewhere, Russian naturally says:

• В предбаннике лежат полотенца.

This is more like:

• The towels are lying in the dressing room than
• There are towels in the dressing room

Although English often just says are, Russian likes to be more specific about position.

The basic form is лежать.

Here is what is happening:

• лежать = infinitive, to lie
• лежат = they lie / are lying

So лежат is:

• present tense
• 3rd person plural

It agrees with полотенца, which is plural.

Because the subject полотенца is plural.

• полотенце = towel
• полотенца = towels

Russian verbs in the present tense agree with the subject in number:

• полотенце лежит = the towel is lying
• полотенца лежат = the towels are lying

So the plural ending -ат matches the plural subject.

Because полотенце is a neuter noun, and its nominative plural form is полотенца.

This pattern is very common for neuter nouns ending in -е:

• море → моря
• поле → поля
• полотенце → полотенца

So полотенца is simply the normal plural form meaning towels.

Both word orders are possible, but they sound a little different in emphasis.

• В предбаннике лежат полотенца
  This often presents the location first, and then tells you what is there. It can feel like: In the dressing room, there are towels / towels are lying there.

• Полотенца лежат в предбаннике
  This starts with the towels and then tells you where they are. It feels more like: The towels are in the dressing room.

Russian word order is more flexible than English, and speakers often move words around to show topic and emphasis rather than changing the basic meaning.

Yes. In many contexts, that is the most natural English translation.

Russian often uses verbs like лежать, стоять, and висеть where English may simply use be:

• Книги лежат на столе. = The books are on the table.
• Стакан стоит на столе. = The glass is on the table.
• Картина висит на стене. = The picture is on the wall.

So while лежат literally includes the idea of lying, English may or may not express that explicitly depending on what sounds natural.

Yes, but it means something a little different.

• В предбаннике лежат полотенца focuses on the towels' position/location.
• В предбаннике есть полотенца focuses more on existence/availability: There are towels in the dressing room.

So if you are simply describing where the towels are, лежат is very natural. If you mean something like the room has towels available, then есть can work.

Лежать is imperfective.

That makes sense because the sentence describes a state, not a completed action:

• лежать = to be lying
• положить = to put down, place
• лечь = to lie down

In В предбаннике лежат полотенца, the sentence is not about someone placing the towels there. It is about their current state: they are lying there.

So yes, aspect matters, but here the imperfective is exactly what Russian normally uses for a continuing situation.

In a way, yes. Russian usually omits the verb to be in the present tense.

English says:

• The towels are in the dressing room.

Russian does not normally say a present-tense equivalent of are here. Instead, it simply says:

• В предбаннике лежат полотенца.

So Russian sentences in the present tense often sound shorter because the present-tense to be is not expressed the way it is in English.