Getting Closed Shells

The atoms reach maximum stability when they achieve completion of their "s" and "p" outer shells. If they have few electrons in the outer shell, they give away those surplus electrons. If they are a few electrons short of a closed shell, they accept the necessary ones from another atom. Accepting or releasing electrons, that's the question. However, the normal situation is that of sharing electrons.
carbon is the master element in the art of sharing electrons!