There are many reasons why pollution in ABC Town is the worst in the world.The topic is “pollution in ABC Town is the worst in the world” and the controlling idea is “many reasons.”
Topic Sentence: To be an effective CEO requires certain characteristics. The topic is “To be an effective CEO” and the controlling idea is certain characteristics.
Topic Sentence: There are many possible contributing factors to global warming.The topic is "contributing factors to global warming" and the controlling factor is "many reasons."
Topic Sentence: Fortune hunters encounter many difficulties when exploring a shipwreck.The topic is “exploring a shipwreck” and the controlling idea is “many difficulties.”
Topic Sentence: Dogs make wonderful pets because they help you to live longer. The topic is "dogs make wonderful pets" and the controlling idea is "because they help you to live longer."
