What it the answer for reader homework

Read the excerpt from it's our world, too! : young people who are making a difference.the author’s purpose in this excerpt is to

He now spent his days in his house, from room to room.which verb best completes the sentence?

"dogs make wonderful pets because they us stay happy and healthy"the topic sentence is "dogs make wonderful pets" i need writing a sentence that is unrelated to the topic and can be eliminated.