Through thorough investigation, Dr. John Snow was finally able to prove that the outbreak of Cholera _____ people’s drinking of polluted water.
He made _____ experiments to prove his theory, and the number _____ added up to 600.
Had it not been for your help, I _____ penniless today.
No one can _____ how to deal with the matter.
No one likes _____ in public.
He was badly hurt last night. That is _____ he didn’t come to school.