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infect - v. to make sick with something that cause disease
uNPRotected - adj. lacking protection or defense; of sexual activity: done without the use of condom to prevent sexually transmitted disease or without the use of birth control to prevent pregnancy
homosexual - adj. sexually attracted to people of the same sex; n. a person who is attracted to people of the same sex, especially a male
virus - n. a kind of organism that causes disease
estimate - v. to form an opinion about a value, size or amout using lessthan complete information
