Sed unknowncommand: ''' (only for fedora18, other systems have not tried, do not know if there is a problem) solved

Sed appears unknowncommand: ''& amp; #39; (only for fedora18, other systems do not try, do not know if there is a problem) solve the sed learning in the past two days, according to your examples, I found some problems. I don't know if it is my fedora18 system. Enter: echoyo... sed appears unknown command: ''' (only for fedora18, other systems do not try, do not know if there is a problem) to solve the sed learning in the past two days, follow your example to practice, but I found some problems. I don't know if it's my fedora18 system. Enter echo you are right | sed \'s/right/wrong/\ '------------------------------ in the terminal and press enter to report the following error: sed:-e expression #1, char 1: unknown command: ''' the above sed command demonstrates how to easily change "right" to "wrong", but an error is returned. The correct information should be: enter echo you are right | sed's/right/wrong/'------------------------------ on the terminal to display: you are wrong note: the escape character "\" cannot appear in the sed command that replaces the string "\"