3．The teens go to sleep later than before because ________.

　　A．melatonin is secreted much later

　　B．melatonin regulates the sleep time

　　C．they sleep a lot in the daytime

　　D．they need to finish their homework

　　解析：选A　细节理解题。根据文章第三段中的“In teens, melatonin is secreted much later in the evening and continues to increase throughout the night.”可知，孩子们睡觉晚是由褪黑激素分泌晚造成的，故A项正确。

　　4．According to AAP's recommendation, middle and high schools should ________.

　　A．let teens sleep in the day

　　B．let the students be active

　　C．delay the start time

　　D．start later at 8 am

　　解析：选C　细节理解题。根据文章最后一段的倒数第二句话可知，APP建议初中和高中上午上课的时间应该推迟，故C项正确。

　　B

　　(2016·沈阳市高三质检)

　　Big messaging apps abroad

　　While WeChat is China's biggest mobile messaging app (应用软件), there are many equivalent apps in other countries that offer similar features.

　　WhatsApp (US)

　　Users: more than 300 million

　　Platforms: Android, iOS, Windows Phone, BlackBerry

　　Features: text chats, push­to­talk, file sharing, location sharing

【2017届高考英语一轮复习跟踪检测：必修2 Module 1 Our Body and Healthy Habits（外研版）】相关文章：

★ 2014届高考英语一轮复习课时作业(八)必修2Module 2《No Drugs》（外研版）

★ 【北师大版】2014届高考英语一轮复习指导课时作业：Unit 7 A卷 Word版含解析

★ 【浙江专用】2014届高考英语一轮复习课时作业(二十五)必修5Unit 5《First aid》

★ 湖南省汝城二中2014届高考英语一轮复习阅读训练 (21)

★ 2017届高考英语二轮复习课时训练：5（含解析）

★ 【三维设计】2017届高考英语（江苏专用）二轮复习课件：必修4 Unit 3《Tomorrow’s world》

★ 【人教版】2014届高考英语一轮复习指导考点针对练：必修4 unit1《Women of achievement》

★ 【优化方案】2017届高考英语二轮复习全国卷Ⅱ规范练：4（含解析）

★ 2014届高考英语一轮复习必修1参考答案（外研版）

★ 【北京专用】2014届高考英语一轮复习方案课时作业：选修7 Unit 3 Under the sea