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herpes- n. a disease that causes painful spots on the ski
plague – n. a change in brain tissue that occurs in Alzheimer's disease
clog – v. to slowly form a block in (something, such as a pipe or street) so that things cannot move through quickly or easily
impressive - adj. deserving attention, admiration, or respect
scream – v. to shout loudly
symptoms –n. a change that shows that a disease is present
bystander – n. someone who is uninvolved in an incident but comes to watch the police or ambulance
microbe – n. an extremely small living thing that can only be seen with a microscope
