World English
English on the internet. The best online resource for English as a second or foreign language (ESL / EFL), English exercises and activities, online English lessons with native speakers of English.www.world-english.org
进入网站 - 2017-09-11可汗学院Khan Academy
Learn for free about math, art, computer programming, economics, physics, chemistry, biology, medicine, finance, history, and more. Khan Academy is a nonprofit with the mission of providing a free, world-class education for anyone, anywhere.
进入网站 - 2013-11-17
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