In bed that night I invented a special drain that would be underneath every pillow in New York, and would connect to the reservo
ir. Whenever people cried themselves to sleep, the tears would all go to the same place.... And when something really terrible happened—like a nuclear bomb, or at least a biological weapons attack—an extremely loud siren would go off, telling everyone to get to Central Park to put sandbags around the reservoir. What assumption does the narrator make in this excerpt?
The assumption that the narrator made on the excerpt is: that many people express their grief through tears.
Assumption refers to the general belief that has not been backed by actual research and concrete data. The way people express grief could be by hiding them inside so other people can't know, by sharing their stories with friends, through the consumption of alcohol, and many other things beside tears.