Learn Turkish: Efendim? Sizi duyamadım. - Pardon? I could not hear you.

Literally, yes. The word efendi means master or sir, and the -m makes it my. However, in everyday Turkish, efendim is the standard, polite way to say Pardon? when you did not catch what someone said. You will also hear it used to answer the phone or to reply when someone calls your name.

Why do we use sizi instead of just siz?

The verb duymak (to hear) requires a specific direct object when you are talking about hearing a specific person. We show this by adding the accusative case ending -i to the formal/plural pronoun siz, giving us sizi.

What is the difference between duymadım and duyamadım?

Duymadım simply means I did not hear. By adding the letter -a- right after the verb root, we get duyamadım, which means I could not hear. That single vowel changes the verb into the negative ability form, showing you were unable to hear despite wanting or trying to.

How exactly do the suffixes in duyamadım break down?

It starts with the root duy- (hear). Next is -a (the negative ability marker indicating inability), followed by -ma (the negative marker), then -dı (the definite past tense marker), and finally -m (the personal ending for I).