A teacher began his class by holding up a glass with some water in it.  He held it up for all to see, and asked the students, ' How much do you think this glass weighs?' '50 g!' '100 g!' '125 g!' the students answered. 'I really don't know unless I weigh it,' said the teacher, 'but my question is what would happen if I held it up like this for a few minutes?' ' Nothing! ' the students said. 'OK. What would happen if I held it up like this for an hour?' the teacher asked. 'Your arm would begin to ache,' said one of the students. 'You're right.  Now, what would happen if I held it for a day?' 'Your arm could go numb. Have to go to hospital for sure!' said another student. All the students laughed. 'Very good. But during all this, did the weight of the glass change?' asked the teacher. 'No.' the students said. 'Then what caused the arm ache and the muscle (肌肉) stress?' The students fell silent for a moment. 'Put the glass down!' said one of the students. 'Exactly!' said the teacher. 'The problems of life are something like this. Hold them for a few minutes in your head, and it seems OK. Think of them for a long time and they begin to make you ache. Hold them even longer and you will not be able to do anything. It's important to think of the  challenges(挑战)  in your life, but it' s even more important to put them down at the end of every day before you go to sleep. That way, you are not stressed. You wake up fresh and strong and can deal with any challenge that comes your way!' Remember to put the glass down today. 小题1: How much do you think this glass which was held by the teacher weighs? A．50g B．125g C．I don’t know. D．100g 小题2: What would happen if the teacher held the glass up like this for an hour? A．One of the students thought his arm could go numb. B．One of the students thought his arm would begin to ache. C．One of the students thought his arm would be changed. D．One of the students thought his arm would be lost. 小题3: Why did the teacher hold up a glass in his class? A．Because he wanted to know how much the glass weighs. B．Because he wanted to ask some student to weigh the glass. C．Because he wanted to make his class more interesting. D．Because he wanted to explain it was important to put the challenges in life down at the end of every day. 小题4: In this passage, the underlined words 'go numb' means_______. A．疼痛不止 B．消瘦萎缩 C．松弛下垂 D．失去感觉 小题5: According to the passage, which of the following is TRUE? A．The teacher told his students to face the challenges bravely. B．The teacher taught his students how to deal with the problems. C．The teacher used to begin his class with a glass of water. D．The teacher usually begins his class by holding a glass of water.