Answer:
Shelley creates tension for the reader by describing in great details the appearances of the monster
Step-by-step explanation:
Shelley creates tension by using flowery language to describe the features of the "monster she created".
She first describes the "dull yellow eyes" of what she created and she also described it as a "catastrophe" that she could not describe.
Another feature that enhanced Shelley's tension created for the readers is the setting and time of the place as it was described as a "dreary night" and it was almost "one in the morning" by the time she was finished.