You now have two sentences left. Take a look at them to see which should come first. Which of the two better connects to the fourth
sentence, and which sentence best wraps up the paragraph? In other words, which sentence doesn’t leave anything hanging at the
end?
S.The porpoise, on the other hand, is fundamentally more like man than like the shark—and it therefore belongs to the order
of mammals.
T.Armed with the knowledge that the porpoise is a mammal, the biologist can then confidently predict that porpoises have a
four-chambered heart and bones of a particular type.
Think about where the paragraph has gone so far. The Topic sentence noted similarities between porpoises and sharks. Sentence R
noted that they were different despite their similarities. Sentence Q identified some differences. Sentence U drew a conclusion about
sharks based on these differences. Sentence S begins by distinguishing porpoises from something mentioned previously—“The
porpoise, on the other hand....” (You know that the porpoise is being distinguished from the shark.) Sentence T then picks up on
the reference to the porpoises as mammals and finishes the idea (i.e., it mentions how scientists can use this data).