Eight alloys were measured before and after tarnish by chromometer.

探讨低贵合金变色的影响因素。

Moisture leads to the tarnish of the silverware.

湿气得银器毫无光泽。

His bad behaviour has tarnished the good name of the school.

他行为不轨, 败坏了学校的声誉。

Brass tarnishes quickly in wet weather.

天气潮湿时黄会光泽。

His reputation was tarnished.

他的声誉受到玷污。