The Internet is increasingly accessible at school and at home. _____many parents and teachers are sometimes not as prepared as we should be to warn children about Internet threats.
People of different countries and regions, different nationalities and cultures have formed with solidarity an Olympic family, ______they have deepened understanding and enhanced friendship.
If there is an intruder _____the campus, students should be _____through an announcement, ______teachers should lock their classrooms to keep the children safe.