20. Which of the following nominating patterns can a teacher adopt to ensure that all students are activity involved in classroom activities?

　　A. Nominating those who are good at English.

　　B. Asking questions in a predicable sequence.

　　C. Nominating students after the question is given.

　　D. Nominating students before giving the question.

　　请阅读Passage 1，完成21~25小题。

　　Passage 1

　　How quickly can you count from one to ten? Do you use ten different words to do it? Can you do it in English, or do you have to use your first languages? Do you count on your fingers? Many people think that numbers and math are the same all over the world. But scientists have discovered that it is not true.

　　People in different parts of the world use different ways to count on their fingers. In the United States, people think begin counting with their first fingers, which they extend or stick out. They then extend the rest of their fingers and finally the thumb(拇指) to count to five. Then they repeat this with the other hand to get to ten. In China, people count by using different finger positions. In this way, a Chinese person can easily count to ten on only one hand.

　　Besides ways of finger counting, scientists have found that cultures and languages are also different when it comes to numbers. Some languages have only a few words for numbers, and others have no words for numbers. A group of scientists studied aboriginal(土著的) people in Australia. These people don’t have hand movements to stand for numbers. They don’t even have word for numbers. However, they are still able to understand different ideas about numbers.

　　In a similar study, researchers from the Massachusetts Institute of Technology discovered that people of the Piraha tribe (部落) in northwestern Brazil don’t have words for numbers such as “one” or “three.”. They are not able to say “five trees” or “ten trees” but can say “some trees,” “more trees,” or “many trees.” Professor Edward Gibson said that mist people believe that everyone knows how to count, “but here is a group that does not count. They could learn, but isn’t not useful in their culture, so they’ve never picked it up.”

　　Although all humans are able to understand quantities(数量),not all languages have numbers and not all people use counting. Number words in a certain language are a result of people needing numbers in their daily lives. Now we know that people have different ideas about numbers and math, too.

　　21. The writer begins with the four questions in order to _____.

　　A. make a survey B. interest readers

　　C. tell a story D. solve math problems

　　22. What do we learn from the difference in finger counting between the U.S. and China?

　　A. People from China count much faster than people from the U.S.

　　B. People from China need two hands to count from one to ten.

　　C. People of different cultures may use different ways of finger counting

　　D. People of different cultures use the same way of finger counting.

　　23. Which of following is true about aboriginal Australians?

　　A. They have only a few words for numbers

　　B. They have hand movements to stand for numbers

　　C. They can only count to five on their fingers

　　D. They can understand different ideas about numbers

　　24. The study of the Piraha tribe shows that _____.

　　A. people all over the world know how to count

　　B. People of the tribe have words for number

　　C. Some groups of people are not smart enough to count

　　D. Counting is not useful in the culture of the tribe

　　25. What is the main idea of the passage?

　　A. people from different cultures have different ideas about numbers and math

　　B. Chinese people can count more easily on their fingers than Americans

　　C. In some aboriginal culture,p eople don’t even know how to count

　　D. Some languages don’t have number words because people don’t need numbers.