The two main kinds of animals are vertebrates and invertebrates. Vertebrates have a backbone and include groups such as mammals, birds, reptiles, amphibians, and fish. Invertebrates, on the other hand, lack a backbone and encompass a diverse range of animals, including insects, arachnids, mollusks, and crustaceans. These classifications help scientists understand the vast diversity and evolutionary relationships among animal species.
The two main kinds are discrete and continuous.
Lion,Cheetah and Tiger.
there are far more than two main kinds of submarines. The only two sections I can think of to separate them are fast attack and Boomers or Ballistic Missle.
There are two main kinds of organisms that have prokaryotic cells: Bacteria and Archaea. These organisms lack a true nucleus and other membrane-bound organelles in their cells.
fat and fur
cat and dog
consumers and producers.
kinetic and potential
indentured and chattel .|.
quiet and explosive
Sail boats and power boats are the two main types of pleasure craft.
The two main types of swamp are "true" or swamp forests and "transitional" or shrub swamps.