Do you know something about the holiday camps in Hong Kong? The students in Hong Kong used to take part in an English holiday camp in their holidays. And their parents weren't with them, though they were very young. Now they still enjoy taking part in many kinds of holiday camps without their parents. Many parents let their children take part in some kinds of holiday camps in order to learn some practical knowledge in their life. And also learn some knowledge about living skills, science, reading and writing... The most important for the children is to learn to look after themselves. Holiday camps in Hong Kong are not so expensive. Most of the families can afford  to send their children there for further study, for making their bodies strong... It is said that students in Hong Kong have much knowledge about many things. Perhaps it has to do with the kinds of holiday camps. When students in Hong Kong are in the holiday camps, their parents   _  .
must be with them have to look after them nearby must stay at home aren't with them