【正文】 is getting _______． A．more and more B．less and less C．cleaner and cleaner D．dirtier and dirtierC When Christopher Columbus landed on the then unnamed Costa Rica in 1502, he saw many Indians wearing gold earrings. So he thought the land must be rich in gold. He named the place Costa Rica, which means “rich coast” in Spanish. Though little gold was found, Costa Rica today is indeed rich with coffee and bananas. Coffee is the most important product in Costa Rica and most of it is exported (出口) to other countries like America and West Germany. Bananas are the country’s second most important export. Costa Ricans also grow many other crops such as fruits, corn and beans for their own use. Costa Ricans love colors and their houses are painted in bright colors. Education is very important to the Costa Ricans. Almost every village has a school and education is a must for children between seven and fourteen years of age. Boys and girls go to separate (單獨的) schools. Classes begin in March and end in November. The other three months of the year are harvest time and the children have to help their parents to pick coffee beans.11. What’s the main idea of the first paragraph? A. How Columbus found Costa Rica. B. How Costa Rica got its name. C. What the Costa Ricans wore. D. What language the Costa Ricans spoke.12. The Costa Ricans may NOT paint their houses ______. A. pink and red B. grey and black C. blue and green D. yellow and orange13. In Costa Rica, boys and girls between seven and fourteen ______. A. must go to school B. study in the same school C. do not have to go to school at all D. can choose to stop schooling at any time14. From December to February, school children in Costa Rica ______. A. have lessons every day B. have their examinations C. help their parents pick coffee beans D. help their parents decorate their houses 15. This passage is mainly about ______. A. Christopher Columbus B. Costa Rica C. some products from Costa Rica D. the education of Costa RicaD It is no surprise to find seashells in the sand. Most seashells are found near the sea. But some seashells have been found on high mountaintops. That is a funny place for seashells. How did they get there? 　　The earth did not always look the way it does today. Once the sea covered mud of the land. Then mountains pushed up. They pushed up through the water. Land from the bottom of the sea became mountaintops. Seashells and fish bones were pushed up, too. They were far away from seawater. They were left high and dry. 　　The seashells and fish bones were covered with soft mud and sand. The mud became hard. It turned to stone. The shapes of the shell and bones were pressed into the stone. These stones are called fossils. 　　Fossils have been found all over our country. H