Η σερβιτόρα μάς φέρνει δύο μερίδες, ένα μπιφτέκι και ένα σουβλάκι.

μάς means us. It is a weak object pronoun, and in Greek these pronouns normally come before a finite verb.

So Greek word order here is roughly:

Η σερβιτόρα μάς φέρνει
= The waitress brings us...

That may feel unusual to an English speaker, because English usually puts us after the verb.

You will often see μας without an accent in everyday writing. The spelling μάς can be used for extra clarity or emphasis, especially to show that it means the object pronoun us rather than a possessive idea like our.

So for a learner, the important thing is:

• μάς / μας here = us

φέρνει is the 3rd person singular present form of φέρνω, meaning bring.

So φέρνει can mean:

• brings
• is bringing

In this sentence, both are natural in English depending on context.

Because δύο μερίδες means two portions / two servings. The part after that tells you what the two portions are:

• ένα μπιφτέκι
• ένα σουβλάκι

So the idea is:

The waitress brings us two portions: one bifteki and one souvlaki.

The foods are singular because each portion is one item.

They are in the accusative, because they are direct objects of φέρνει.

A useful thing to know is that in Modern Greek some accusative forms look the same as nominative forms:

• μπιφτέκι and σουβλάκι are neuter singular, so nominative and accusative are identical
• μερίδες also has the same form in nominative and accusative plural

So even though the case is accusative, the form does not visibly change here.

Greek normally repeats the numeral/article when listing separate counted items:

• ένα μπιφτέκι
• και ένα σουβλάκι

That makes it clear that there is one of each. Repeating ένα sounds natural and standard.

Not quite. μπιφτέκι usually means a ground-meat patty, often grilled. It is closer to burger patty or meat patty than to a full hamburger in a bun.

So if you translate it simply as burger, be aware that the Greek word often refers to the meat itself, not the sandwich.

The comma introduces an explanation of what the two portions are. It works a bit like namely or a soft pause in English:

δύο μερίδες, ένα μπιφτέκι και ένα σουβλάκι
= two portions, one bifteki and one souvlaki

It helps the sentence read naturally, but the main grammar is the same either way.

A rough pronunciation guide:

• μπιφτέκι ≈ bee-fTEH-kee
• σουβλάκι ≈ soov-LAH-kee

Useful pronunciation points:

• μπ at the start of a word is usually pronounced like b
• ου sounds like oo in food
• the written accent shows the stressed syllable

So the stress is on:

• -τέ- in μπιφτέκι
• -λά- in σουβλάκι

Yes. Greek word order is more flexible than English word order. This sentence uses a very natural neutral order:

Η σερβιτόρα μάς φέρνει δύο μερίδες...

But Greek could move things around for emphasis, for example:

• Μας φέρνει η σερβιτόρα δύο μερίδες...
• Δύο μερίδες μάς φέρνει η σερβιτόρα...

The basic meaning stays the same, but the emphasis changes.