Many birds live in cities where they make their homes in special places like attics (the space under the roof), on the edges of tall buildings, or in little holes in bridges. When winter comes and it gets cold, people help the birds by putting bird feeders filled with seeds on windows and in trees so the birds have something yummy to eat.
We can also say it like this: Birds choose cozy spots in the city to build nests, such as under roofs or on tall walls. During cold weather, kind people hang bird feeders on trees or near windows to give birds food and keep them strong.