题目内容：

请用适当的词完成下面的短文。每个空只能写一个形式正确、意义相符的单词。

     Today, an increasing number of people are always looking at their mobile phones with their heads down. These people are 1.  the “Heads-down Tribe”. Heads-down tribe members now can be seen everywhere.

     There are more and more traffic 2. because lots of drivers use mobile phones while driving. In order to make drivers pay more 3. to driving, some new traffic rules have been made.

     As we can see above, using mobile phones may 4. traffic accidents. Also, more and more interesting and strange facts happen to the “Heads-down Tribe”. A man in America kept 5. his mobile phone on his way home. As  6. result, he knocked into a big lost bear. When he lifted  7. eyes from the phone, he was so afraid that he turned around and ran away as 8. as possible. Another fact is that we can often see people in the restaurant eating face to face but looking at their own mobile phones. It’s strange 9. they don’t talk to the ones who sit opposite to them during the meal. Some of them even have fun communicating with others on the phone.

     Mobile phones are helpful and necessary tools for modern life. Whether they are good or not depends  10. how people use them. Let’s be “healthy” users and try to be the “Heads-up Tribe”.