Onda sam bila bolesna.

to be

Breakdown of Onda sam bila bolesna.

• bolestan: sick or ill
• onda: then

Questions & Answers about Onda sam bila bolesna.

What is the basic structure of Onda sam bila bolesna?

It breaks down like this:

• Onda = then, at that time
• sam = I am in its clitic form, but here it helps make the past tense
• bila = been / was feminine past participle of biti (to be)
• bolesna = sick / ill feminine adjective

So the structure is roughly:

• Onda
  • sam bila
    • bolesna
• Then
  • I was
    • sick

In natural English, this is simply Then I was sick or At that time I was sick.

Why is sam used here if the sentence means I was, not I am?

Because Serbian commonly forms the past tense with:

• a present-tense form of biti (to be)
• plus a past participle

So sam bila means I was.

For the verb biti, the past tense works like this:

• ja sam bio / bila = I was
• ti si bio / bila = you were
• on je bio = he was