练习材料：

[Day 1746 2019-07-08]

Lesson 18-3 Porpoises

This is not easy, and may require two porpoises working together. In another

game, as the turtle swims across the oceanarium, the first porpoise swoops down from

above and butts his shell with his belly. This knocks the turtle down several feet. He no

sooner recovers his equilibrium than the next porpoise comes along and hits him

another crack. Eventually the turtle has been butted all the way down to the floor of the

tank. He is now satisfied merely to try to stand up, but as soon as he does so a porpoise

knocks him flat. The turtle at last gives up by pulling his feet under his shell and the

game is over.

任务配置：L0+L1+L4

知识笔记：

oceanarium    n. 大型海洋水族馆;

swoops down    向下俯冲

butts    v. (人) 用头顶撞; (动物) 用头(或角)顶;    n. (武器或工具的) 粗大的一端; 烟蒂; 烟头; (盛液体的) 大桶;

equilibrium    n. 平衡; 均衡; 均势; (心情、情绪) 平静，安宁; 心理平衡;

knocks him flat    把他击倒在地

练习感悟：