Ο βαθμός τριμήνου δείχνει τη σχολική επίδοση.

Ο is the masculine singular definite article, meaning the.

So ο βαθμός = the grade / the mark.

Greek nouns have grammatical gender, and βαθμός is a masculine noun. That is why it takes ο in the nominative singular.

A few basic article forms for comparison:

• ο = masculine singular nominative
• η = feminine singular nominative
• το = neuter singular nominative

So in this sentence, ο βαθμός is the subject of the verb.

In this sentence, βαθμός means grade, mark, or score.

It can also mean other things in different contexts, such as:

• degree
• level
• rank

But in a school context, βαθμός most naturally means a student's grade/mark.

Because τριμήνου is in the genitive case.

The basic noun is:

• το τρίμηνο = the trimester / the term

But here Greek is expressing the idea grade of the term / trimester, so it uses the genitive:

• βαθμός τριμήνου = term grade / literally grade of trimester

So:

• nominative: το τρίμηνο
• genitive: του τριμήνου

In this sentence, the noun appears in genitive form without the article:

• τριμήνου

That is very common in Greek in this kind of compact expression.

Greek often leaves out the article in expressions like this when one noun modifies another.

So:

• ο βαθμός τριμήνου = the term grade
• literally: the grade of term

You could also see fuller phrases with an article, depending on context, such as:

• ο βαθμός του τριμήνου = the grade of the trimester

That version sounds more explicitly like the grade of the specific term.

The version in your sentence, ο βαθμός τριμήνου, is more compact and label-like, which is very natural in school or administrative language.

Δείχνει is the 3rd person singular present tense of the verb δείχνω = to show.

So it can mean:

• he shows
• she shows
• it shows

Here the subject is ο βαθμός τριμήνου, which is singular, so Greek uses δείχνει = shows.

A few forms of δείχνω:

• δείχνω = I show
• δείχνεις = you show
• δείχνει = he/she/it shows
• δείχνουμε = we show
• δείχνετε = you all show
• δείχνουν(ε) = they show

Because it is the direct object of δείχνει, so it must be in the accusative case.

The basic noun is:

• η επίδοση = the performance / achievement

In the accusative singular, it becomes:

• την επίδοση

The adjective σχολική also has to match the noun in:

• gender: feminine
• number: singular
• case: accusative

So:

• τη(ν) σχολική επίδοση = the school/academic performance

This whole phrase is the object of the verb:

• shows the academic performance

In Modern Greek, the final -ν of την is often dropped before certain consonants.

So both of these may occur:

• την σχολική επίδοση
• τη σχολική επίδοση

Before a word starting with σ, dropping the -ν is very common, so τη σχολική επίδοση sounds perfectly normal.

You will see the same thing with other articles and pronouns too, for example:

• τον φίλο often keeps the -ν
• τη μητέρα may drop it depending on the following sound
• δε(ν) also behaves similarly in some contexts

In short, τη σχολική επίδοση is just a normal phonetic/spelling variant of την σχολική επίδοση.

Σχολική means school-related or academic, and επίδοση means performance or achievement.

So σχολική επίδοση means:

• school performance
• academic performance
• school achievement

In natural English, academic performance is often the smoothest translation.

Because Greek commonly places adjectives before the noun, especially in straightforward descriptive phrases.

So:

• η σχολική επίδοση = the academic performance

That said, Greek can also place adjectives after the noun in some contexts:

• η επίδοση η σχολική would sound marked or unnatural here
• η επίδοση στο σχολείο would mean something a bit different

For this sentence, η σχολική επίδοση is the normal order.

The word order can change, because Greek has more flexibility than English thanks to its case system.

The sentence as given:

• Ο βαθμός τριμήνου δείχνει τη σχολική επίδοση.

is a normal, neutral order:

• subject + verb + object

But Greek could change the order for emphasis, for example:

• Τη σχολική επίδοση δείχνει ο βαθμός τριμήνου.
• Δείχνει τη σχολική επίδοση ο βαθμός τριμήνου.

These are still understandable, but the original order is the most straightforward and standard for learners.

Yes. That is a good way to understand it structurally.

Greek often uses a pattern like:

• noun + genitive noun

to express relationships that English often shows with of or by using a noun as an adjective.

So:

• βαθμός τριμήνου literally = grade of term naturally = term grade

Other similar patterns:

• βιβλίο μαθητή = student's book / book of a student
• αίθουσα διδασκαλίας = classroom / literally room of teaching

So yes, this is a very useful structure to learn.

There are two main clues:

1. The article and noun are in the nominative form

   • ο βαθμός = nominative singular masculine

2. The verb agrees with it

   • δείχνει = 3rd person singular
   • ο βαθμός τριμήνου is singular, so that matches

Meanwhile, τη σχολική επίδοση is clearly the object because it is in the accusative.

So the structure is:

• Ο βαθμός τριμήνου = subject
• δείχνει = verb
• τη σχολική επίδοση = object

Yes, επίδοση is a common word, especially in education, sports, and evaluation contexts.

It often means:

• performance
• achievement
• attainment

For example:

• σχολική επίδοση = academic performance
• αθλητική επίδοση = athletic performance

By contrast, απόδοση often means:

• output
• yield
• efficiency
• rendering/translation in some contexts

So in a school sentence, επίδοση is the more natural choice for performance/achievement.

That would also be correct:

• Ο βαθμός του τριμήνου δείχνει τη σχολική επίδοση.

This version is a bit more explicit:

• the grade of the trimester/term

The original:

• Ο βαθμός τριμήνου

is more compact and often sounds like a fixed label or category, similar to how English says term grade.

So the difference is not that one is right and the other is wrong; it is more about style and phrasing.

A rough pronunciation guide is:

• Ο βαθμός τριμήνου δείχνει τη σχολική επίδοση
• o vath-MOS tree-MEE-noo THEEH-khnee tee skho-lee-KEE eh-PEE-tho-see

A few helpful notes:

• θ sounds like th in think
• δ sounds like th in this
• χ is a rough sound, like German Bach or Scottish loch
• Stress matters a lot in Greek, so pay attention to:
  • βαθμός
  • τριμήνου
  • δείχνει
  • σχολική
  • επίδοση

The accent marks show which syllable is stressed.