If there is an intruder _____the campus, students should be _____through an announcement, ______teachers should lock their classrooms to keep the children safe

None of the students watched the teacher______

Did you enjoy your time in the concert— Yes, I have never been to _________ one before.

_______ her husband，she has now become a famous movie star.

The H7N9 flu is reported ______ higherfever and coughing for several days.