spark plugg are burnt

I'll try and post from a computer later I'm on my phone I was trying to find a app but no luck. I have two plugs that don't have nonfoulers that are good the others have the electroid burned up. Not sure what the latter is is that the hook at the top if so I got one spark plug with a Chuck of that gone. The other three are missing the electrode. I'm looking to keep this engine alive hopefully through the summer. One more question why am I having problems with just four plugs and not all six. Two plugs look perfect with no non foulers. Thanks for the help and suggestions guys.