The Sentence Diagram Generator visually represents the grammatical structure of the sentence: "Sharks have a good sense of smell but when their eyesight is poor." It will illustrate the main clause "Sharks have a good sense of smell" and the subordinate clause "when their eyesight is poor," along with the coordinating conjunction "but" connecting the two clauses. The diagram will show the subject "Sharks," the verb "have," and the object "a good sense of smell," while also depicting the dependent clause structure for clarity.