Το κατάστημα δίπλα στην πλατεία κλείνει νωρίς τον Αύγουστο.

Το κατάστημα means the shop/store, and it is in the nominative case because it is the subject of the sentence — the thing that does the action.

• το = the for a neuter singular noun
• κατάστημα = shop / store

So:

• το κατάστημα = the shop

Greek nouns have grammatical gender, and κατάστημα is neuter, so it takes το.

Because δίπλα normally works with σε when you say what something is next to:

• δίπλα σε... = next to...

So the full structure is:

• δίπλα σε την πλατεία

But in normal Greek, σε + την contracts to:

• στην

So:

• δίπλα στην πλατεία = next to the square

Using η πλατεία would not work here, because after δίπλα σε, Greek needs the noun in the form used after σε, not the plain subject form.

Στην is just the contracted form of σε την.

• σε = in / at / to
• την = the (feminine accusative singular)

So:

• σε την πλατεία → στην πλατεία

This contraction is extremely common in Greek.

You will also often see:

• στο = σε το
• στους = σε τους
• στις = σε τις

Yes. After σε, Greek uses the accusative case.

The noun πλατεία is feminine, and in this sentence its form is:

• nominative: η πλατεία
• accusative: την πλατεία

Because the phrase is really σε την πλατεία, the noun is in the accusative.

In this particular word, πλατεία looks the same in nominative and accusative singular, but the article shows the case clearly:

• η πλατεία = subject form
• την πλατεία = object / after preposition form

Κλείνει is the 3rd person singular present tense of κλείνω.

It can mean:

• closes
• shuts
• sometimes, depending on context, is closing

In this sentence, it means that the shop closes early during August.

So:

• κλείνει νωρίς = it closes early

Because the subject is singular:

• Το κατάστημα = the shop

So the verb must also be singular:

• το κατάστημα κλείνει = the shop closes

If the subject were plural, the verb would change. For example:

• Τα καταστήματα κλείνουν = The shops close

Νωρίς is an adverb. It means early.

It describes how / when the shop closes:

• κλείνει νωρίς = closes early

It does not change form for gender, number, or case.

In Greek, expressions of time such as months, days, and some other time phrases are often put in the accusative.

So:

• ο Αύγουστος = August (nominative)
• τον Αύγουστο = in August / during August

This is very normal Greek usage.

Similar examples:

• τον Ιούλιο = in July
• τη Δευτέρα = on Monday
• τον χειμώνα = in winter

Greek often uses the definite article with months, even where English does not.

So:

• τον Αύγουστο means in August
• not literally in the August in natural English

This is one of those places where Greek and English structure things differently. The article is normal and expected in Greek.

Usually, in a sentence like this, τον Αύγουστο means in August / during August.

Depending on context, it can sometimes refer to a specific upcoming or recently mentioned August, but by itself it is often just the normal way to say in August.

So the exact nuance depends on the situation, but grammatically the phrase itself is standard for in August.

Yes, Greek word order is more flexible than English.

The sentence as given is very natural:

• Το κατάστημα δίπλα στην πλατεία κλείνει νωρίς τον Αύγουστο.

But you could also hear variations such as:

• Τον Αύγουστο το κατάστημα δίπλα στην πλατεία κλείνει νωρίς.
• Το κατάστημα δίπλα στην πλατεία τον Αύγουστο κλείνει νωρίς.

These versions shift the emphasis slightly, but the basic meaning stays the same.

Greek often moves time expressions like τον Αύγουστο for focus or style.

It is often taught as an adverb or as part of a prepositional expression.

On its own:

• δίπλα = next to / beside / nearby

But when it introduces what something is next to, it usually appears with σε:

• δίπλα σε κάτι = next to something

So in this sentence:

• δίπλα στην πλατεία = next to the square

For learners, the most useful thing is simply to remember the pattern:

• δίπλα σε + noun

Yes. Κατάστημα is a general word that can mean:

• shop
• store
• business premises

Which English word sounds best depends on context. In many sentences, both shop and store are fine translations.

Greek present tense can cover both ideas, depending on context.

So κλείνει can mean:

• a general/habitual fact: it closes early in August
• a present-time situation: it is closing early in August

In this sentence, the most natural reading is the habitual/general one: during August, that shop has earlier closing hours.

Context would tell you if the speaker means a one-time temporary situation or a recurring schedule.