のだとう translation

[nonezumi]

Hello,

Please kindly help me with のだろう translation in the sentence below.
I could translate it as "probably" but i am not sure if i am right.

らくに なった のだろう つるは うれしいそうに ぱたぱたと はばたきを
してみせた。

Probably felt revealed and look happy, crane showed it by wings flapping.

Thank you very much!

 

[undrentide]

Your interpretation is correct, ～のだろう is a phrase to assume the cause/reason.
のだろう ＝ の ＋ だろ ＋ う
の (nominalizer)
だろ＞だ (auxiliary verb for assertion)
う (auxiliary verb for presumption)

https://ja.wikipedia.org/wiki/%E5%8A%...8F.A3.E8.AA.9E
Conjugation of だ（未然形）

 

[nonezumi]

Thank you very much for your kind help!