No one has seen a flock of birds like this in years, he thought.
They look like a flock of birds taking off from the bottom.
The great hall was filled with a flock of birds.
A flock of birds might drive a powerful animal away from food.
Finally you spot something coming south, but it's a flock of birds.
A flock of small black birds came across the building in a desperate way.
It would be like a flock of birds in flight.
They are usually found in small flocks of less than ten birds.
What looked like a flock of birds rose from deep in the city and headed our way.
High in the air there were flocks of dark birds.
I mean, flights of birds are quite complex, but these were words.
His main interest was in aviation, the problems of bird flight.
In the distance there was a flight of birds, south, away from the guns.
It seemed to have no more to do with us than a flight of birds.
He waved his hand in the air as if describing the flight of birds.
For example, he studied the flight of birds to find means by which humans could fly.
It arises in the flight of both aircraft and birds.
Overhead, a flight of birds was passing across the forest.
He'd look, I don't joke, at things like the flight of birds.
Finally, theories on the evolution of bird flight are discussed.