How does the writer use conflict and comparison and contrast of beowulf and unferth to develop or support meaning/theme?

These themes stated, the most universal is good verses evil. Unferth is presented as contrast to Beowulf, providing a glimpse of a poor warrior in contrast to Beowulf's good warrior. ... Unferth does become more generous after Beowulf defeats Grendel, and lends Beowulf his family sword to fight Grendel's mother.

the statement flat characters usually only have one trait that is developed in their story lines is true.

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).