Sentence 1: Jimmy took his dog for a walk. 
 Sentence 3: Jimmy and his dog played in the park 
 Sentence 4:  It began raining so Jimmy and his dog walked back home 
 Sentence 5:  Jimmy and his dog got home but they were all wet 
 Option 1: While walking they stopped by the shop. 
 Option 2: While walking they stopped by the park.