Sentence 1: It was a cold winter morning. 
 Sentence 3: Her dog got sick with a cold because of the cold weather 
 Sentence 4:  Jill took her dog to the vet 
 Sentence 5:  The vet prescribed some cold medicine for her dog 
 Option 1: Jill had to let her dog out in the morning. 
 Option 2: Jill had to let her dog out in the morning but will never go to the vet.