A felhasználó megnézi az e-mailt.

Both a and az mean the.

The choice depends on the sound that follows:

• a before a consonant sound: a felhasználó
• az before a vowel sound: az e-mailt

So this is similar to English a / an, except in Hungarian it happens with the, not with the indefinite article.

The -t is the accusative ending, which marks the direct object of the verb.

Here, the email is the thing being looked at / checked, so Hungarian marks it:

• az e-mail = the email
• az e-mailt = the email as a direct object

English usually shows this by word order, but Hungarian often marks objects directly with a suffix.

The prefix meg- changes the meaning.

• nézi = looks at, watches
• megnézi = looks at/checks/views with a more complete or result-oriented sense

With something like an email, megnézi is very natural because it suggests checking or taking a look at it.
So megnézi az e-mailt is closer to checks the email than to simply is looking at the email.

Because Hungarian uses the definite conjugation when the verb has a definite direct object.

Here the object is definite:

• az e-mailt = the email

So the verb is:

• megnézi = he/she checks it / the specific thing

Compare:

• megnéz egy e-mailt = he/she checks an email
  Here the object is indefinite, so the verb is megnéz
• megnézi az e-mailt = he/she checks the email
  Here the object is definite, so the verb is megnézi

This definite vs. indefinite verb system is one of the big differences between Hungarian and English.

No. Hungarian does not have grammatical gender like English he/she.

felhasználó simply means user, without saying whether the person is male or female.
The verb megnézi also does not show gender.

So the sentence itself does not tell you whether the user is a man or a woman.

No, Hungarian word order is more flexible than English word order.

A felhasználó megnézi az e-mailt. is a neutral, natural sentence order:

• topic/subject: A felhasználó
• verb: megnézi
• object: az e-mailt

But Hungarian can change word order for emphasis or focus.

For example, moving something before the verb can highlight it. So the order is not just about grammar; it is also about what the speaker wants to emphasize.

Yes, often you can omit the subject in Hungarian if it is already clear from context.

For example:

• Megnézi az e-mailt.

This can mean He/She checks the email, or in some contexts polite You check the email.

Hungarian often leaves subjects unstated when they are understood.
But in your sentence, A felhasználó is included because the speaker specifically wants to say the user.

Grammatically, it is present tense.

But in Hungarian, the present tense can sometimes also be used for:

• habitual actions
• scheduled actions
• near-future actions

So depending on context, megnézi az e-mailt could mean:

• The user checks the email
• The user is going to check the email

Without context, the most basic reading is simple present.

Yes. It is a loanword, but Hungarian still adds Hungarian endings to it.

So:

• e-mail = email
• e-mailt = email + accusative -t

This is very common in Hungarian: foreign words can keep their original-looking spelling, but they still behave like Hungarian words grammatically and take Hungarian suffixes.

Yes. Felhasználó is built from the verb felhasznál, which means use or utilize, plus the ending -ó, which can form a person doing the action.

So literally it is something like:

• felhasznál = to use
• felhasználó = user, literally one who uses

This kind of word formation is very common in Hungarian.