如何健康减少咖啡因摄入
Many students in the US drink coffee, tea or cola every day. These drinks all have caffeine (咖啡因) in them.
Caffeine can make people feel awake. It can also change their feelings. Some students drink a lot of cola. Then they cannot sleep well at night.
Now some students want to drink only a little. But this can make them have a tough time. In the first few days, these students may feel tired. Some feel unhappy. Some get angry easily. A few of them have a headache.After two weeks, most of them feel good again. They have a lot of energy in the day. They sleep well at night. They feel happy.
But it is different for different people. Some people feel worried easily. The change is big for them. For other people, the change is small.
Doctors say, “Do not stop quickly. Have a small cup every day. Drink water, not cola.” Slowly, you can feel fine again.
1.1. What can caffeine do to people?
A It can make them feel awake.
B It can help them sleep well.
C It can make them feel tired.
D It can make them feel calm.
解析：选A。A 细节理解题。原文第二段第一句“Caffeine can make people feel awake.”直接说明咖啡因能让人感到清醒。B“帮助睡好”与原文不符，原文说喝大量可乐会睡不好，减少咖啡因两周后才睡得好；C“让人感到累”是减少咖啡因后最初几天的反应，不是咖啡因本身的作用；D“让人感到平静”与原文“change their feelings”“worried”等不符。故选A。
2.2. How may students feel in the first few days?
A Happy and strong.
B Fine and calm.
C Tired and unhappy.
D Busy and cold.
解析：选C。C 细节理解题。第三段明确说“In the first few days, these students may feel tired. Some feel unhappy.”即最初几天可能感到累、不开心。A“开心强壮”是两周后大多数人的状态；B“很好平静”与最初几天的不适相反；D“忙碌寒冷”文中没有提到。故选C。
3.3. What does the underlined word “tough” mean?
A Great.
B Hard.
C Easy.
D Boring.
解析：选B。B 词义猜测题。画线词“tough”所在句说“这可能会让他们度过一段tough的时期”，后面紧接着列举“tired, unhappy, get angry easily, headache”等负面反应，说明tough表示“困难的、难受的”，因此选“Hard”。A“Great”是正面词；C“Easy”是反义词；D“Boring”表示无聊，和上下文不符。故选B。
4.4. What can we know from Paragraph 4?
A All people feel the same.
B People have different changes.
C Everyone feels worried.
D Few people have changes.
解析：选B。B 推理判断题。第四段先说“But it is different for different people.”然后举例说明有人容易担心、变化大，有人变化小。由此可以归纳出“人们的变化不同”。A“所有人都一样”与段首相反；C“每个人都担心”把原文中的“Some people”扩大为“Everyone”；D“几乎没人有变化”与“变化大/变化小”矛盾。故选B。
5.5. What is the text mainly about?
A Ways to make cola drinks.
B Rules for good sleep.
C Advice on cutting caffeine.
D Reasons for liking coffee.
解析：选C。C 主旨大意题。全文从含咖啡因的饮料谈起，接着讲学生减少咖啡因时会出现不适，最后引用医生建议“不要快速停止，每天喝一小杯，喝水而不是可乐”，核心是关于如何减少咖啡因摄入的建议，所以选“Advice on cutting caffeine”。A“制作可乐饮料的方法”只在开头提到可乐，不是重点；B“良好睡眠的规则”只是部分内容；D“喜欢咖啡的原因”文中没有展开。故选C。