regex - Sed: How to replace a string which includes multiple special characters? -

I try to comment on a line in / etc / sudoers via a shell script I am doing This is the relevant line I would like to edit:

  # grep '\! Requite '/ etc / sudoers default: nagios! Requiretty  

But it seems that the way I am using with sed is wrong, my attempt is:

  # sed -i 's / ^ default \: nagios $ / # default: ngosos! Jurority / G / E / Sdoders # sed -i 's / ^ Defaults: Nagoya $ / #defaults: Nagas! Zeri / G '/ At / Esdoes # SAD-Eye' s / ^ Default: Nagian $ / # Default: Nagois! Zeri / G '/ etc / sudoers # sed -i' s / ^ Default: nagios $ / \ # Default: nagios! Requiretty / g '/ etc / sudoers # sed -i' s / ^ Default: nagios $ / \ # Default: Nagas \! Zeri / G '/ etc / Sueders # sed -i' s / ^ Default: Nagoya $ / ^ # Default: Nagios! Zeri / gi '/ etc / sudoers # sed -i' s / ^ default \: nagios $ / ^ # default: Nagas! Zeri / gi '/ etc / sudoers # sed -i' s / ^ basics \ nagios $ / # default: nagios \! Requite / g '/ etc / sudoers  
  
 Thanks in advance  
  
 
 
 Good ...  sudoers  is not writeable by anyone - even root too. You want to edit it with the command  visudo  instead of for security reasons. 
 
 I think you can look back at it, though  sed  is the replacement  find . The second part is the replacement. So you want to do something like this: 
 
  sed -i 's / ^ basics: nagios! Requite $ / # Default: 'nagios /'  
 
 This will also remove  kititi  if you want you to go to  #  If you want to add, you can do this: 
 
  sed -i 's / ^ default: nagios! Requiretty $ / # & amp; / '