Using "Since" and "For" with the Present Perfect

source: English Lessons with Alex    2009年8月15日
http://www.engvid.com/ Depending on whether you want to talk about how long you have been doing something, or when you started doing something, you will need to use one of these two words. Find out which is which and take the free quiz on the lesson at http://www.engVid.com/

# relevant grammar videos: present perfect + "since" or "for"