Moje konto jest zablokowane, więc nie mogę się zalogować.

Because konto is a neuter noun in Polish.

Polish adjectives and possessive words have to agree with the noun’s gender, number, and case.

• mój = for masculine singular nouns
• moja = for feminine singular nouns
• moje = for neuter singular nouns

So:

• mój telefon = my phone
• moja książka = my book
• moje konto = my account

Since konto is neuter, moje is the correct form.

It is in the nominative case.

In this sentence, konto is the subject:

• Moje konto = my account

The sentence is basically structured like:

• My account
  • is blocked

Subjects normally appear in the nominative in Polish, so konto stays in its dictionary form here.

Jest zablokowane means is blocked.

This is made of:

• jest = is
• zablokowane = blocked

The word zablokowane is a participle/adjective-like form that agrees with konto:

• konto is neuter singular
• so the form is zablokowane

Compare:

• Telefon jest zablokowany = The phone is blocked.
• Karta jest zablokowana = The card is blocked.
• Konto jest zablokowane = The account is blocked.

So the ending changes depending on the gender of the noun.

Yes, in practice that is a very useful way to think about it.

It comes from the verb zablokować = to block, but in a sentence like this it behaves much like an adjective:

• konto jest zablokowane = the account is blocked

So for a learner, it is often easiest to understand it as a describing word formed from a verb, similar to English blocked.

Więc means so, therefore, or thus.

It introduces a result:

• Moje konto jest zablokowane, więc nie mogę się zalogować.
• My account is blocked, so I can’t log in.

It connects the two ideas:

1. the account is blocked
2. as a result, logging in is impossible

Because Polish normally uses a comma before conjunctions like więc when they join two clauses.

Here we have:

• Moje konto jest zablokowane
• więc nie mogę się zalogować

These are two separate clauses, so the comma is standard and expected.

Nie mogę means I cannot or I’m not able to.

The verb is móc = to be able to, can.

Its first-person singular form is:

• mogę = I can

With negation:

• nie mogę = I can’t

So:

• mogę się zalogować = I can log in
• nie mogę się zalogować = I can’t log in

Because zalogować się is the normal Polish verb meaning to log in.

The się is part of the verb expression. Very often, Polish verbs that describe actions done by the subject to themselves or are just fixed idiomatic forms use się.

So you should learn this as a unit:

• zalogować się = to log in
• wylogować się = to log out

Even though English just says log in, Polish uses the form with się.

Both word orders are possible.

You can say:

• nie mogę się zalogować
• nie mogę zalogować się

The first version, nie mogę się zalogować, is usually the more natural and common one in everyday Polish.

This is because się is a very mobile word in Polish and often appears before the infinitive.

So in this sentence, the placement of się is normal and idiomatic.

This is about aspect.

Polish verbs often come in pairs:

• logować się = imperfective
• zalogować się = perfective

Very roughly:

• logować się focuses on the process or repeated action
• zalogować się focuses on the completed result: successfully logging in

In this sentence, nie mogę się zalogować sounds natural because the idea is I can’t manage to log in / I can’t complete the login.

You may also hear nie mogę się logować, but that would suggest more of a repeated or ongoing inability, depending on context.

Yes. In many contexts, zalogować się can correspond to English log in or sign in.

The exact English translation depends on the system or website, but the Polish verb stays the same.

So all of these may fit depending on context:

• I can’t log in
• I can’t sign in

In this sentence, yes, jest is normally included.

Polish often omits forms of to be in the past in some structures? No—but in the present tense, with a predicate like this, jest is standard:

• Moje konto jest zablokowane.

Leaving it out would sound incomplete or nonstandard in ordinary Polish.

So unlike Russian, for example, Polish normally keeps jest in a sentence like this.

Mogę is pronounced approximately like MOH-gheh with a nasal ending.

A few helpful points:

• g is always a hard g, as in go
• the stress is on the first syllable: MO-gę
• ę is a nasal vowel, though in normal speech it is often not pronounced as a strong nasal sound in every position

At the end of a word, ę is often pronounced less distinctly nasal than learners expect. So mogę may sound closer to mogeh with some nasal coloring, depending on the speaker.

It is completely normal and neutral. It works well in both everyday and formal situations.

You could use it:

• in customer support
• in an email
• in a chat message
• when speaking to a help desk

It does not sound unusually formal or unusually casual.

Yes, but it means something slightly different.

• Moje konto jest zablokowane = My account is blocked.
  
  • focuses on the current state
• Moje konto zostało zablokowane = My account was blocked / has been blocked.
  
  • focuses more on the event of it being blocked

In your sentence, jest zablokowane is very natural because the important point is the present result: the account is currently blocked, so logging in is impossible.

Not completely, but the given version is the most natural neutral order.

Standard version:

• Moje konto jest zablokowane, więc nie mogę się zalogować.

You could rearrange parts for emphasis, but that would usually sound less neutral.

For example:

• Nie mogę się zalogować, bo moje konto jest zablokowane.

That means almost the same thing, but now the sentence begins with I can’t log in rather than My account is blocked.

So the original word order is a very good default to learn.