concern
v.
early 15c., "perceive, distinguish," also "refer to, relate to," from Middle French concerner, from Medieval Latin concernere "concern, touch, belong to," figurative use of Late Latin concernere "to sift, mix, as in a sieve," from Latin com- "with" (see com-) + cernere "to sift," hence "perceive, comprehend" (see crisis). Apparently the sense of the prefix shifted to intensive in Medieval Latin. Meaning "worry" is 17c. Related: Concerned; concerning. Letter opening to whom it may concern attested by 1740.
n.
1580s, from concern, v..
〔李〕[con-(com-)=thoroughly彻底地；cern=to separate区分→“to separate thoroughly in the mind心里区分得一清二楚”→“to interest oneself very much非常感兴趣”→] I v. ① involve or worry（oneself）关心；牵挂