The phrase "are major features" is correct and usable in written English.
It can be used when describing significant characteristics or elements of a subject or topic.
Example: "The new software update includes several enhancements that are major features aimed at improving user experience."
Alternatives: "are key aspects" or "are significant elements".
For example, eyelid skin cancers in xeroderma pigmentosum and retinal dystrophy in Cockayne syndrome are major features of these syndromes.
Altered cellular bioenergetics and mitochondrial function are major features of several diseases, including cancer, diabetes, and neurodegenerative disorders.
Reduction of prepulse inhibition (PPI) of acoustic startle response, locomotor hypoactivity, bilateral striatal lesions as well as brain oxidative stress are major features of HD.
The widely used even-age management including small and uniformly sized regeneration areas together with the small-patterned private ownership are major features reshaping the Finnish forest structure.
Clearing for large-scale soy production and the displacement of cattle-breeding by soybeans are major features of land-use change in the lowland Amazon that can alter hydrologic properties of soils and the runoff generation over large areas.
What I have described are major features of traditional Chinese thought.
Augustin Daly, in full John Augustin Daly, (born July 20 , 1838 Plymouth, North Carolina, U.S. died June 7 , 1899 Paris, France), American playwright and theatrical manager whose companies were major features of the New York and London stage.
Satire and black humour were major features of many of his films, and his performances had a strong influence on a number of later comedians.
Epilepsy and/or movement disorder were major features in all 21.
The fatique and somatic factor symptoms, including irritability, may be major features of major and in particular of melancholic depression [ 49].
Other ziyarets are major land features and pilgrimage sites where miracles are said to have occurred.
