Sentence 1: Tony needed to get gas on his way home. 
 Sentence 3: When he went to pay for it, he was didn't owe anything 
 Sentence 4:  Someone else had already paid for a full tank of gas for him 
 Sentence 5:  Tony felt double blessed after getting gas on his way home 
 Given Sentence 2: He only had enough money to fill half of his tank.