How to use "ulla" in a sentence

It was a sad movement between two notes, 'Ulla, ulla, ulla, ulla,' continuing without stopping

'Ulla, ulla, ulla,' cried that inhuman note - great waves of sound sweeping down the broad, sunlit road, between the tall buildings on each side

'Ulla, ulla, ulla,' cried the voice, coming, it seemed to me, from the district around Regent's Park

I awoke to find that sad howling still in my ears: 'Ulla, ulla, ulla, ulla, ulla,' It was now getting dark, and after I had found some bread and cheese in the bar I walked on through the silent squares to Baker Street and so came at last to Regents Park

That non-stop sound of 'Ulla, ulla, ulla, ulla' confused my mind

Then the sound of 'Ulla, ulla, ulla, ulla' stopped