Sentence 1: Sam was leaving to surprise his girlfriend in China tomorrow. 
 Sentence 3: In the middle of packing he gets a knock at his door 
 Sentence 4:  His girlfriend showed up to surprise him 
 Sentence 5:  He would have been a bit more excited if his ticket was refundable 
 Given Sentence 2: The gas from the lantern spilled out and caught on fire.