Feynman et al，Thees are the lectures in physics that I gave last year and the year before to the freshman and sophomore classes at Caltech.The lectures are，of course，not verbatim-they have been edited，sometimes extensively and sometimes lessso.The lectures form only part of the complete courese.The whole group of 180students gathered in a big lecture room twice a week to hear these lectres and then they broke up into small groups of 15 to 20 students in recitation sections under the guidance of a teaching assistant.In addition，there was a laboratory session once a week.　　　　此书为英文版。