WHY IS MY CAR NOT STARTING?

i have 1999 Volvo s80. The car turns over and sounds like is it about to start but doesn't. I changed the battery cause i thought it was dead but it still did the same thing. I had the alternator replaced about a year ago i dint know if it broke again. How do I check? I Thinks it is a fuse or chip something electrical. if that maybe the problem which one is it?WHY IS MY CAR NOT STARTING?it's either fuel or fire. could be a bad fuel pump or could be a fouled spark plug. It really depends on a lot of different things. are you sure that you have gas...the gas gauge could be bad...check this too.WHY IS MY CAR NOT STARTING?The ignition could be broken.