11.   As the ear hears birds chirping, separate cells respond to each frequency while others compute the direction and intensity of the sound.

12.   Birds could be heard through the rumble, and graveyards and unopened schools flashed by outside the windows.

13.   For the first time, you could hear the birds chirping in the branches.

14.   He heard birds singing, then noticed a white, shining cloud and around it a rainbow of colors.

15.   He hears the birds chirping and hears the voices of the children.

16.   I can hear the bird beating its wings against the folding glass doors that close off the fireplace, and I have to do something about it.

17.   I heard birds singing in the pine trees nearby.

18.   I can still hear the birds that were out there that day.

19.   I hear birds.

20.   Not even a bird can be heard.