Are you carrying too much on your back at school? You’re not alone. Back experts(专家) in the USA are worried about that young students are having back and neck problems because they are carrying too much in their backpacks .
“It hurts my back when I run,” said Ebelin Reyes, a student in Virginia. “It’s hard to get up the stairs with my backpack because it’s too heavy.” Students have to carry heavy backpacks on their backs for a whole week’s study. Ebelin is one of them. They have   regular(固定的)backpacks with two straps(带子) to carry them, but a number of students with heavy loads(负担) have switched to rolling backpacks. The backpacks have wheels and can roll on the ground. Shirley Park’s backpack weighs 10 kilos, and she said, “I’ll change to a rolling backpack because I am starting to have back pain.”
How much is too much? Experts say that students should carry no more than 10% to 15% of their own body weight. A few students have had a good idea to lighten(减轻) the load: less homework.
Doctor’s suggestions:
Lighten the load. Take home only the books the students need that day.
(2) Wide straps are better. They can send out weight over your shoulders (肩)and be sure to wear backpacks with two straps.
(3) The heaviest things should be packed closest to the back.
(4) Bend(弯曲) both knees when you pick up the pack, don’t just bend over the waist(腰).
【小题1】The main idea of the passage is about _______.

The teacher stood before his class of 30 students and was going to hand out the final exam papers. “I know how hard you have all worked to get ready for this test. ” he said. “And because I know you are all able to understand these questions. I am ready to offer a B to anyone who would prefer not to take the test. ’’
A number of students jumped up to thank the teacher and left the classroom. The teacher looked at the rest students and said. “Does anyone else want to get a B? This is your last chance. ”Two more students decided to go. Seven students stayed. The teacher then handed out the papers. There were only three sentences on the paper： Congratulations! You have received an A in this class. Keep believing in yourself.
I never had a teacher who gave a test like that. but I think that it is a test that any teacher could and should give. Students who do not have confidence in what they have learned are B students at most.
The same is true for students in real life. The A students are those who believe in what they are doing because they have learned from both successes and failures. They have learned life’s lessons. whether from school education or from events in their lives，and have become better people. Scientists say that by the age of eight，80% of what we believe about ourselves has already been formed. You are a big kid now and you realize that you have some limits(局限). However，there is nothing you can’t do or leant to be. Sir Edmund Hillary, the first person to reach the top of Mount Qomolangma (珠穆朗玛峰)said，“We do not conquer the mountain, but ourselves. ”
【小题1】Some students left the classroom because _________.

Are you carrying too much on your back at school? You’re not alone. Back experts(专家) in the USA are worried about that young students are having back and neck problems because they are carrying too much in their backpacks .

“It hurts my back when I run,” said Ebelin Reyes, a student in Virginia. “It’s hard to get up the stairs with my backpack because it’s too heavy.” Students have to carry heavy backpacks on their backs for a whole week’s study. Ebelin is one of them. They have   regular(固定的)backpacks with two straps(带子) to carry them, but a number of students with heavy loads(负担) have switched to rolling backpacks. The backpacks have wheels and can roll on the ground. Shirley Park’s backpack weighs 10 kilos, and she said, “I’ll change to a rolling backpack because I am starting to have back pain.”

How much is too much? Experts say that students should carry no more than 10% to 15% of their own body weight. A few students have had a good idea to lighten(减轻) the load: less homework.

Doctor’s suggestions:

Lighten the load. Take home only the books the students need that day.

(2) Wide straps are better. They can send out weight over your shoulders (肩)and be sure to wear backpacks with two straps.

(3) The heaviest things should be packed closest to the back.

(4) Bend(弯曲) both knees when you pick up the pack, don’t just bend over the waist(腰).

1.The main idea of the passage is about _______.

A．the problems made by rolling backpacks

B．the advantage of backpacks

C．the best backpacks for students

D．how to lighten students’ backpacks

2.From what Ebelin Reyes and Shirley Park said, we know______.

A．students like to carry heavy backpacks

B．students have to do a lot of homework

C．backpacks with wheels are bad for students

D．students have no time to play because of heavy backpacks

3.The underlined word “switch to” means______.

A．use for           B．turn to            C．catch up          D．begin to use

4.According to the experts, it’s better for a student of 40 kilos to carry a backpack of ____ at most.

A．10 kilos           B．8 kilos            C．6 kilos            D．7 kilos

5.If students follow the doctor’s suggestions, they______.

A．may do less homework

B．may feel their backpacks are lighter

C．can learn how to enjoy themselves

D．will know why to wear heavy backpacks

The number of the students _______ 1200. A number of students _______absent （缺席）yesterday.

The number of the students in our school _________ 600, but a number of students _________ living in the school.