What does a newborn swallow look like?

The newborn swallow looks like the picture below:

After growing for a period of time, as shown in the following figure:

Little swallows are called young swallows, generally referring to swallows that have not left their nests and need to be fed by their parents. Swallow is a general term for 74 species of passeriformes. Small size, narrow wing tip, short beak and concave tail, weak feet and few feathers. Feathers are monochromatic, blue or green, with metallic luster; Most kinds of men and women are very similar. Swallows spend a lot of time catching pests in the air. It is one of the most flexible birds, mainly feeding on insects such as mosquitoes and flies, and is a well-known beneficial bird. Nest in tree holes or cracks, or make holes in sand dikes, or stick mud on walls or protrusions of corridors, roofs, eaves, etc. In urban and rural areas. 3 pounds per work? Seven eggs.