source

n. /sɔːrs/ A2

来源；源头

The place, person, or thing that something comes from.

仙境例句

Alice heard deep, sad sighs, and their source was the Mock Turtle, alone on his rock.

爱丽丝听见一声声深深的、伤心的叹气，原来是假海龟独自坐在石头上发出来的。