Rocks are commonly divided into three major classes according to the processes that resulted in their formation.
These native elements are commonly divided into three groups namely, metals (platinum, iridium, osmium, iron, zinc, tin, gold, silver, copper, mercury, lead, chromium); semimetals (bismuth, antimony, arsenic, tellurium, selenium); and nonmetals (sulfur, carbon).
Intentionality is commonly divided into three constitutive features.
The life cycle of fibre metal laminates subjected to mechanical fatigue is commonly divided into three stages: crack initiation, crack propagation, and final failure.
Mood disorders are commonly divided into three major categories: unipolar mood disorders (major depressive disorder, dysthymic disorder), bipolar mood disorders (bipolar I disorder, bipolar II disorder, cyclothymic disorder) and mood disorders with a known aetiology (substance-induced mood disorder, mood disorder due to a general medical condition) (American Psychiatric Association 2000).
The Brenner corridor is commonly divided into three sections: Northern access route (Munich – Kufstein, Kufstein – Kundl, Kundl – Baumkirchen); Brenner Base Tunnel (Innsbruck – Fortezza/Franzensfeste) with the Innsbruck bypass; Southern access route (Fortezza/Franzensfeste – Ponte Gardena/Waidbruck, Bolzano/Bozen bypass, Trento bypass, Verona approach).
Professional training of veterinarians is commonly divided into two phases.
In more-detailed classification schemes based on character of eruption, volcanic activity and volcanic areas are commonly divided into six major types, shown schematically in the diagram.
Soil organisms are commonly divided into five arbitrary groups according to size, the smallest of which are the protists including bacteria, actinomycetes, and algae.
Computer printers are commonly divided into two general classes according to the way they produce images on paper: impact and nonimpact.
The lying down sequence is commonly divided into five stages.
