"<span>As of some one gently rapping, rapping at my chamber door."</span>
Education and learning do have to do with contagiousness and infection. When a teacher teaches something, it is kind of like a contagious disease. You pass that information on to others very quickly. It "infects" your brain in such a way that retains that info so that it can be used in the long run.
Complex sentence because 'when i visited Issac's house' could not be a sentence on its own but 'his parents gave me a warm welcome' could