Νιώθω ότι μαθαίνω πιο εύκολα ελληνικά όταν μιλάω για καθημερινά πράγματα, όπως ένα σάντουιτς, μια σαλάτα με φέτα ή ένα μπολ με φρούτα.

Ότι means that and introduces a clause, just like in English:

• Νιώθω ότι μαθαίνω...
• I feel that I learn... / I feel like I learn...

So Νιώθω = I feel, and ότι μαθαίνω πιο εύκολα ελληνικά... is the idea being felt.

A useful pattern is:

• Νομίζω ότι... = I think that...
• Ξέρω ότι... = I know that...
• Νιώθω ότι... = I feel that...

In everyday English, we often drop that. Greek can also sometimes omit ότι, but here it sounds very natural.

Because the sentence is talking about a general, ongoing experience, not a single completed event.

• μαθαίνω = I learn / I am learning
• θα μάθω = I will learn
• έμαθα = I learned / I found out

Here the speaker means something like:

I feel that I learn Greek more easily when I talk about everyday things.

That is a general truth or repeated situation, so the present tense is the normal choice.

Πιο εύκολα is an adverbial expression meaning more easily.

• εύκολος / εύκολη / εύκολο = easy (adjective)
• εύκολα = easily (adverb)

Here it modifies the verb μαθαίνω:

• μαθαίνω πιο εύκολα = I learn more easily

Greek often forms this kind of comparison with:

• πιο + adverb/adjective = more ...

So:

• εύκολα = easily
• πιο εύκολα = more easily

You may also see more formal comparative forms, but πιο εύκολα is very common and natural.

In Greek, names of languages are normally written with a lowercase letter unless they begin a sentence.

So:

• ελληνικά = Greek
• αγγλικά = English
• γαλλικά = French

Greek also often uses language names without an article after verbs like learn, speak, know, etc.

• μαθαίνω ελληνικά = I’m learning Greek
• μιλάω αγγλικά = I speak English

That is completely normal.

Yes, literally it is present tense, but in Greek the present tense is often used for repeated actions or general situations after όταν.

So:

• όταν μιλάω για καθημερινά πράγματα
  = when I talk about everyday things

This does not necessarily mean one specific moment right now. It means whenever I talk about everyday things or when I’m talking about everyday things in general.

That is very natural Greek.

Yes, both are correct.

• μιλάω = common, everyday form
• μιλώ = also correct, sometimes a bit more formal or concise

So these both mean I speak / I talk:

• μιλάω ελληνικά
• μιλώ ελληνικά

In this sentence, μιλάω sounds very natural and conversational.

After για (about / for), Greek normally uses the accusative case.

So:

• για πράγματα = about things

πράγματα is the accusative plural of πράγμα (thing).

The adjective καθημερινά agrees with πράγματα:

• πράγματα = neuter plural
• καθημερινά = neuter plural form of καθημερινός (daily / everyday)

So:

• καθημερινά πράγματα = everyday things

Here όπως means such as or like, introducing examples.

• όπως ένα σάντουιτς, μια σαλάτα με φέτα...
• such as a sandwich, a salad with feta...

It is often used to give examples after a general category:

• φρούτα, όπως μήλα και πορτοκάλια
  = fruits, such as apples and oranges

So in this sentence, καθημερινά πράγματα is the general category, and the foods are examples.

Because Greek nouns have grammatical gender, and the indefinite article changes to match the gender.

The basic forms are:

• ένας = masculine
• μια / μία = feminine
• ένα = neuter

In your sentence:

• σάντουιτς is treated as neuter → ένα σάντουιτς
• σαλάτα is feminine → μια σαλάτα
• μπολ is neuter → ένα μπολ

So you choose the article based on the noun’s gender, not on natural gender or English habits.

Με usually means with.

So:

• σαλάτα με φέτα = salad with feta
• μπολ με φρούτα = bowl with fruit / a bowl of fruit

In English, we often say a bowl of fruit, but Greek commonly uses με here:

• ένα μπολ με φρούτα literally = a bowl with fruits

So the Greek structure is slightly different from the most natural English translation, but it is completely normal Greek.

Because when Greek talks about an ingredient or material in a general way, it often does not use the article.

So:

• σαλάτα με φέτα = salad with feta
• μακαρόνια με τυρί = pasta with cheese
• ψωμί με βούτυρο = bread with butter

If you say με τη φέτα, it sounds more specific, like with the feta—a particular feta already known in the conversation.

Here the meaning is general, so με φέτα is the natural choice.

Yes, Greek often uses the plural φρούτα when talking about fruit as pieces or kinds of fruit in a bowl.

• ένα μπολ με φρούτα = a bowl with fruit / a bowl of fruit

In English, fruit is often uncountable, but Greek commonly uses the plural φρούτα in this kind of context.

You may also see singular φρούτο, but that usually means:

• a fruit as one item, or
• fruit in a more abstract/general sense

Here φρούτα feels more natural because a bowl usually contains several pieces.

Σάντουιτς is a loanword from sandwich. In modern Greek, many loanwords are either partly or fully indeclinable, meaning their form often stays the same.

So you may see:

• ένα σάντουιτς
• το σάντουιτς

The word does not change much, unlike many native Greek nouns. That is normal and common with borrowed words.

Yes, it could, but the nuance changes slightly.

• καθημερινά πράγματα = everyday things
• καθημερινά θέματα = everyday topics

In this sentence, πράγματα feels broad and natural, especially because the examples are simple objects/foods.
Θέματα would sound a bit more like subjects of conversation.

So the original wording is very natural for casual speech.

It helps to break it into pieces:

• Νιώθω = I feel
• ότι = that
• μαθαίνω πιο εύκολα ελληνικά = I learn Greek more easily
• όταν μιλάω για καθημερινά πράγματα = when I talk about everyday things
• όπως... = such as...

So the full structure is:

I feel [that I learn Greek more easily] [when I talk about everyday things], [such as ...]

This kind of long sentence is very common in Greek. If you can identify the main verb first (Νιώθω) and then the clause after ότι, it becomes much easier to follow.