一、读句子，选择正确的答案。
()1. Which one is different from the others?

()2. Which shape can you often see in the supporting structures(支架结构) of a building or a bridge(桥)?

()3. Look at the pictures. How many pictures can you draw at one stroke only(只用一笔)?
A. 1.
B. 2.
C. 3.
D. 4.

1.C 2.B 3.B

二、读一读，算一算。
1. What is the next number? 2,3,5,9, .
2. What is the next number? 4,6,10,14,22, .
3. Try to give the value of each other.（请根据下列等式，算出各字母的值）
A+B=195 B+C=188 A+C=193
A= B= C=
4. I saw some ducks yesterday. They were walking in a line to the river. One baby duck was walking between two baby ducks, one baby duck was walking behind two baby ducks, and the first duck was walking in front of the three baby ducks. How many ducks did I see yesterday?

5. If an astronaut(宇航员) has a weight of 72 kg on the Earth(地球), he will have a weight of 12 kg on the Moon. If another astronaut has a weight of 10.5 kg on the Moon, what will the astronaut's weight be on the Earth?

1. 17
2. 26
3. A=100 B=95 C=93
4. 4/Four ducks.
5. 63 kg.