Read the excerpt from Poe’s "The Fall of the House of Usher." I dared not -- oh, pity me, miserable wretch that I am! -- I dared not -- I dared not speak! We have put her living in the tomb! Said I not that my senses were acute? I now tell you that I heard her first feeble movements in the hollow coffin. I heard them -- many, many days ago -- yet I dare not -- I dared not speak! What is the effect of parallelism in this excerpt?