touchstone
touchstone
noun
noun
- a piece of fine-grained dark schist or jasper formerly used for testing alloys of gold by observing the colour of the mark which they made on it
试金石
■a standard or criterion by which something is judged or recognized
检验标准
they tend to regard grammar as the touchstone of all language performance.
他们往往把语法作为所有语言运用的检验标准。
考试词汇表
