plumb-line
柯林斯詞典
1. N-COUNT A plumb line is a piece of string with a weight attached to the end that is used to check that something such as a wall is vertical or that it slopes at the correct angle. 鉛垂線(xiàn)
返回 plumb-line
1. N-COUNT A plumb line is a piece of string with a weight attached to the end that is used to check that something such as a wall is vertical or that it slopes at the correct angle. 鉛垂線(xiàn)