The phrase "comprises the majority" is correct and usable in written English.
You can use it to indicate that something forms the majority of a group or a whole. For example, "The region comprises the majority of the population of the country."
The first group comprises the majority of patients undergoing major surgery, who are at risk of significant volume shifts during surgery because of bleeding or other significant intravascular volume losses.
Amylopectin, the major component of starch, is moderately branched, comprises the majority of starch mass, and is responsible for the crystallinity of starch granules.
Refinancing comprises the majority of mortgage applications.
Beta-thalassemia comprises the majority of all thalassemias.
Type I collagen comprises the majority of the total body collagens.
In fiscal year pay 2018, stock-based compensation comprises the majority of CEO pay at S&P 500 and S&P 400 companies for the first time.
Our local community comprises the majority of the patients for whom we care, and there is a deep-rooted culture of service within our department.
Twitter comprises the majority (77%) of the over 5 million relevant English posts, far ahead of Tumblr (4%), Facebook (3%), YouTube (3%), and Google Plus (<1%).
White adipose tissue, or white fat, comprises the majority of fat in our bodies; its purpose is to store energy for future use.
Specifically, these novel scaffolds mirror the nanofibrous collagen network that comprises the majority of the non-mineral portion of bone matrix.
Several big city police departments are majority-black or majority-Hispanic (Atlanta, Birmingham, Detroit, Washington, Miami, Santa Fe and El Paso, for instance), while others (such as Chicago) are so diverse that no single group comprises the majority.
