1、Collins
http://www.collinsdictionary.com/
?
2、Merriam-Webster
?
http://www.merriam-webster.com/
?
3、Oxford
http://www.oxforddictionaries.com/
?
4、Cambridge
http://dictionary.cambridge.org/
?
5、Longman
http://global.longmandictionaries.com/
?
6、Macmillan
http://www.macmillandictionary.com/
?
7、Heritage
?
?
?
?
?
原文：http://yangshangchuan.iteye.com/blog/2217191