A few blind people have mastered echolocation in order to sense their surroundings .
有些盲人已经掌握了通过超声定位来感知周围环境的技能。
Zappos has also mastered the art of telephone service-a black hole for most internet retailers .
zappos还掌握了电话服务的艺术对于多数网上销售商来说是个黑洞。
In addition to the specific knowledge they have mastered in their discipline , nearly all graduate students have learned advanced communication and research skills which can be applied to many high-level jobs in the government and corporate sectors .