Ο γιατρός ελέγχει τον εγκέφαλο.

the doctor

Breakdown of Ο γιατρός ελέγχει τον εγκέφαλο.

• ελέγχω: to check
• ο εγκέφαλος: brain

Questions & Answers about Ο γιατρός ελέγχει τον εγκέφαλο.

What does ο mean here?

Ο is the masculine singular definite article in the nominative case. In this sentence, it means the and goes with γιατρός.

So:

• ο γιατρός = the doctor

Greek articles change form depending on gender, number, and case, so you will not always see the same form for the.

Why is it τον εγκέφαλο and not ο εγκέφαλος?

Because τον εγκέφαλο is the direct object of the verb.

Greek shows the job of a noun by using case:

• ο εγκέφαλος = nominative, used for the subject
• τον εγκέφαλο = accusative, used for the direct object

In this sentence, the brain is being checked, so it is the object, not the subject.

Why does εγκέφαλος change to εγκέφαλο?

This is a normal noun change for many masculine nouns ending in -ος.

For this pattern:

• nominative singular: ο εγκέφαλος
• accusative singular: τον εγκέφαλο

So the ending changes from -ος to -ο in the accusative singular.

Another common example:

• ο άνθρωπος
• τον άνθρωπο

How do I know the doctor is the one doing the action?