Many people belive that a bird's home and place to sleep is its nest, but is that true?
Zoologists have found that birds don't roost overnight in their n____ ,even if a storm is coming . Ducks and swans often hide their heads u____ their wings and float on the water at night.Cranes are fond of sleeping on the ground.
Since they don't s____ in the nests , why do birds still build nests? Birds usually lay and hatch eggs in their nests.After the birds are hatched,the nests become places for the m___ birds to take care of their chicks. The nests soon become crowded as the chicks g____ .After some time, there is no longer r_____ for the mother birds in the nests .
