Sentence 1: Cass loved sweet potatoes. 
 Sentence 3: However, he could not cook them 
 Sentence 4:  He tried a recipe and they never came out right 
 Sentence 5:  Cass finally gave up 
 Option 1: His mom would always make them for him. 
 Option 2: His mom taught him how to make them so he cooked them himself.