You will be given a definition of a task first, then some input of the task.
In this task, you're given an article and an answer. Your task is to generate the fill-in-the-blank question for this answer based on the given article. The blanks are always at the end of the question, and can be filled with more than one word or phrase.

Article: Sydney Australia--Mobile phone has become a problem for middle schools. Some middle schools in Australia have banned students from carrying mobile phones during school hours. Mobile phone use among children has become a problem for the school this year. Several children have got mobile phones as Christmas gifts, and more students want them. Mary Bluett, an official, said mobile phone use is a distraction to students during school hours and it also gives teachers so much trouble in their classrooms. Teachers were also saying that sometimes students might use phone messages to cheat during exams. She said some schools had tried to ban mobile phones. Some parents felt unhappy because they couldn't get in touch with their children. Many teachers said students should not have mobile phones at school, but if there was a good reason, they could leave their phones at school offices. They also said there were many reasons why the students should not have mobile phones at school: _ were easy to lose and were a distraction from studies. Many people say that they understand why parents would want their children to have phones, but they think schools should let the students know when they can use their mobile phones.
Answer: because they are young
Output:
Some middle schools in Australia have banned students from carrying mobile phones _ .