The purpsose of this assignment is to create a multimedia presentation to convince a group of your peers to join you in taking a stand on an important global issue that impacts the future

the following key ideas correctly express the key sentence.

restate key idea: most people can learn to swim in ten short lessons.

restate key idea: the majority of water-accident victims require mouth-to-mouth breathing.

restate key idea: an empty, tightly closed gallon jug will support a tired swimmer.  

restate key idea: first aid is to prevent accidents as well as assist in rescue.

explanation: the key idea needs to have the same topic as the key sentence (drowning and safety).

can you give me a hint

i'm thinking it would be when compound subjects are joined by or, nor,either-or, neither-nor.