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хорошо изученный stresses
gen.	well-studied (bugrym); highly researched (Ying); well traveled (nikitaAprelkov)
math.	thoroughly studied
progr.	well-known (пример ssn)
scient.	well characterized (Игорь_2006)
хорошо изучить
idiom.	know the ropes (что-либо Andrey Truhachev)
хорошо изучен
math.	is well understood

хорошо изученный: 10 phrases in 5 subjects

General	3
Mathematics	2
Pharmacology	2
Pharmacy and pharmacology	1
Programming	2