***** NOT A TEACHER *****
(1) I have lived in the United States since 1937. (When did it begin?)
(2) Therefore, I have lived in the United States for 75 years. (How much time?)
(3) Mr. Barak Obama has been the president of the United States since January, 2009. (When did it begin?)
(4) Mr. Barak Obama will have been the president of the United States for four years by January, 2013. (How much time?)
*****
(5) I have been typing this post since 11:15 a.m., Pacific Standard Time.
(6) It is now 11:25. So I have been typing this post for 10 minutes. (I am a very bad typist!)
