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основная причина stresses
gen.	rationale; reason fundamental; key reason (Alex_Odeychuk); leading cause (Franka_LV); prime mover (National economic policy and taxation were seen as the prime movers in the rankings, in which six of the top 10 cities were in Asia. TMT Alexander Demidov); the root cause of (чего-либо Alex Pike); chief cause; major reason (ssn); prime reason (Ремедиос_П); underlying reason (Andy); bottom line; primary cause (Alex_Odeychuk)
Игорь Миг	key; crux
adv.	prime cause; primary cause (Alexander Demidov)
amer.	main culprit (ухудшения ситуации; Children in this ​country are getting much too ​fat, and ​sugar and ​sweets are the ​main culprits. Val_Ships)
automat.	root cause (напр., неисправности)
avia.	main cause (ЛП)
busin.	driving factor (Alex_Odeychuk); core reason
dipl.	ultimate cause
energ.ind.	root cause (напр., аварии, события, отказа оборудования и т.п.)
fin.	main reason (dimock)
law	basic cause; primary reason
Makarov.	fundamental cause; fundamental reason
math.	dominant cause (доминирующая); major cause; principal cause; root cause
med.	primary cause (ЛП); prime cause (ЛП)
progr.	root cause (неработоспособности; причина дефекта, при обнаружении и удалении которой появление дефектов (неисправностей) этого вида исключается (или сокращается) ssn)
scient.	upstream cause (iKar_Don)
основные причины
progr.	underlying factors (ssn)

основная причина: 96 phrases in 22 subjects

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