垃圾待运点定期洗刷，做到无（）。
A.污水流淌
B.无蝇蛆
C.无积垢无恶臭味
D.无污点
参考答案：A, B, C
两个质数的和是24，较小质数是较大质数的几分之几？较大质数是较小质数的多少倍？（用假分数表示）
Directions: Look at the following picture and write an article on eager learners. Your article should meet the following two requirements:
1) Interpret the message conveyed by the picture.
2) Make your comments on the phenomenon.
You should write about 160 -200 words neatly on ANSWER SHEET 2. (20 points)
