In most cases, carbon shares electrons with other atoms (usual valence of 4). This is because carbon typically bonds with elements which have a similar electronegativity. Examples of covalent bonds formed by carbon include carbon-carbon, carbon-hydrogen, and carbon-oxygen bonds
Wanted to write more both there is a problem with the editor. Uranium is formed naturally in the crust of rocks and seawater. Plutonium does not occur in nature. It is found in the biosphere.
