Well, right now you are going to learn the biggest reasons why your gas stove burners can stop working, how to troubleshoot them, and what you need to replace to fix the problem.
This will actually be pretty simple to get you back up and running. When you turner your gas burner knob to the light position, this sends a signal to the spark modulator, then the spark modulator sends the spark to the burners, easy enough right.
First thing we need to do is identify the problem that your having so I can tell you where to look. So here is example problem number one. When you turn the front right burner to light, nothing happens but you can hear the gas. All the rest of the burners work fine. Too make this easy, you have a bad ignitor wiring harness. This is the piece that goes around each burner valve and tells the spark modulator that you are in the light position on one of the burners. These come as an assembly, so if one is bad you end up replacing them for all your burner valves.
Here is example problem number two. When you try to turn on the front right left burner, all the other burners spark, except the front left. Well, you have a bad spark modulator. When it receives the signal from one of the burner valves that its time to light, it sends a spark to all the burners. Each burner has its own wire that comes from the spark modulator. Now you have one burner with no spark, some of these are wired together, so one wire will control the two left side burners and the other wire will control the two right side burners. If that's the case then if part of the spark modulator went bad then you would loose spark to half your burners. Got it?
OK, here is the last, but most common problem that you will have with your stove, I saved the best for last. Here are the symptoms of problem number three. You turn your burner to light, the burner you are trying to light has spark, but it won't light and you can light it with a match. This one is going to be just a little difficult to explain, but I will try my best. In the area of the burner where your see the spark, behind the little white piece there is a hole, this hole goes into the center of the burner. This is where the gas initially lights to light the whole burner. If that little hole gets plugged with grease and grim, the gas cannot get to the spark and light the fire. Usually a needle of some sort is what you would use to clean the hole. If you closely inspect this with a flashlight you will see what I'm talking about. I have a thin piece of wire that I carry with me when I'm out doing service just for this reason.
Thanks Again and Good Luck with your Repair!