光是绿色植物制造有机物不可缺少的条件．（判断对错）

甲、乙两人参加植树活动，两人共植树20棵，已知甲植树数是乙的1.5倍、如果设甲植树x棵，乙植树y棵，那么可以列方程组（　　）

根据短文理解，从A、B、C、D四个选项中选择最佳一项填空。

　　How do you imagine the future? Will life in the future be better, worse or the same as now? 1 do you think of the future?

People 2 that life will probably be very different in 2050. First of all, planes will be very 3, so flying will be very cheap. Everyone will have a small car. Fuel will be new and clean, but expensive. We will 4 robots everywhere. And space planes will take us around the world 5 two hours. Homes will be warm in winter and cool in summer, so they will be very comfortable. We will use the sun 6 our homes. Computers will be very small so they will be very 7. People will do many things on the Internet.

At that time, water will become one of our most8 problems. In many places, farmers will be in great need of water to9 fruit and vegetables.

    By 2050, we will be able to help blind and deaf people see again and10 again. At that time, our life will be better and better.

鲁博士公休仪
公仪休者，鲁博士也。以高第①为鲁相。奉法循理，无所变更，百官自正。使食禄者不得与下民争利，受大者不得取小。
客有遗相鱼者，相不受。客曰：“闻君嗜鱼，遗君鱼，何故不受也？”相曰：“以嗜鱼，故不受也。今为相，能自给鱼；今受鱼而免，谁复给我鱼者？吾故不受也。”
【注释】①高第：考试及考核官吏成绩优等。