= the limit of sb's responsibility, interest, or activity; range of experience or thought
* run sb/sth into the ground = ~À» ³ìÃʰ¡ µÇµµ·Ï ÀÏÀ» ½ÃŰ´Ù, ~À» ¸Á°¡Áöµµ·Ï ¾²´Ù
= to cause sb to become exhausted; to destroy or ruin sth through neglect or misuse