Most bullying (恃强凌弱) is found in schools where there is a tarmac (柏油碎石) playground; the least bullying is in a natural area that the children are encouraged to explore.
出自-2010年12月阅读原文
柯林斯高阶英汉双解学习词典释义
N-UNCOUNT
(铺路面用的)柏油碎石
Tarmac is a material used for making road surfaces, consisting of crushed stones mixed with tar.