语言学
双数的(古英语、希腊语等名词、动词等除有单复数变化外，还有双数变化)
The Highways Agency says dualling the road will cut down on accidents and improve journey times.
BBC: NEWS | UK | England | Norfolk | Concerns over A11 bypass scheme
The A465 Heads of the Valleys "dualling" programme has been split into six sections.
BBC: ?150m A465 Heads of the Valleys road project awarded
After securing European funding, the Welsh government said dualling of the Brynmawr to Tredegar road could progress.
BBC: Heads of the Valleys A465 upgrade after ?82m funding
英汉双解词典包含3185865条英汉词条，基本涵盖了全部常用单词的翻译及用法，是英语学习的有利工具。