Students mark the main ideas and important details with a pen or pencil, yellow or blue or orange.
出自-2014年6月听力原文
Why did the Federal Aviation Authority require the black boxes be painted orange or yellow
出自-2010年6月阅读原文
The same year, the Federal Aviation Authority required that the boxes, which were never actually black, be painted orange or yellow to aid visibility.
出自-2010年6月阅读原文