---What ______ the noise, Bill?---Sorry, I broke my glass.
—Can the plane fly _____ the Atlantic Ocean? —Yes,but it needs to go_____the clouds for hours.
—Can you tell me _____when the teacher came into the classroom? —Sorry,I don’t know.
The teacher said that _____ of the boys would take part in the fashion show.
—______ did your sister leave China? —She______ for three years .
—How are you getting on with your study,Tom? —So far,I____very well at school.