题目

根据短文内容，在文中空格处填上一个恰当的词，使短文完整、通顺。No one can live without sleep. Experts believe that sleep is 【1】 food and water. Good health needs good sleep. Scientists have found that people who sleep for less than 6 hours and a half at night are more often ill than people 【2】 sleep for 8 hours.How 【3】 hours do you sleep every night? Most students have less than 8 hours of sleep every night. Some teachers complain that a few students feel sleepy or even fall asleep in class. These students can 【4】 concentrate(集中注意力）on t名著导读。　　这一夜我的睡眠很不好，希望和恐惧轮流地在我心中转来转去。我起来好几次……最后可纪念的8月19日那天，早晨六点，客厅门打开，尼摩船长进来，他对我说：“到自由通行的海了！　　上面文字出自法国作家______的名著《____________》，尼摩船长的话表明此时他们已经摆脱困境，他们遇到的这个困境是：_______________________。