diving ducks of North America having a bluish-grey bill
双语例句
1. Lesser Scaup Aythya affinis, Northern Pintail Anas acuta, and several sea ducks are showing troubling declines, but most geese are increasing dramatically and many ducks have held steady.
2. Lesser Scaup Aythya affinis, Northern Pintail Anas acuta, and several sea ducks are showing troubling declines, but most geese are increasing dramatically and many ducks have held steady.