Through thorough investigation, Dr. John Snow was finally able to prove that the outbreak of Cholera _____ people’s drinking of polluted water.
Don't worry. I'm sure things will get better.
Tom was about to close the window ________ his attention was caught by a bird.
With so many noises from the busy traffic in the street, I couldn’t______ and do my research work.
You _______ here last week if you were really worried about your work.
The wooden house______ by many trees_______ south.