练习材料：
[Day 1745 2019-07-07]
Lesson 18-2 Porpoises
Porpoises and sharks are natural enemies. It is possible that upon such an occasion
a battle ensued, with the sharks being driven away or killed.
Whether it be bird, fish or beast, the porpoise is intrigued with anything that is
alive. They are constantly after the turtles, who peacefully submit to all sorts of
indignities. One young calf especially enjoyed raising a turtle to the surface with his
snout and then shoving him across the tank like an aquaplane. Almost any day a young
porpoise may be seen trying to turn a 300-pound sea turtle over by sticking his snout
under the edge of his shell and pushing up for dear life.
任务配置：L0+L1+L4
知识笔记：
ensued v. 接着发生; 因而产生;
intrigued adj. 着迷; 很感兴趣; 好奇; v. 激起…的兴趣; 引发…的好奇心; 秘密策划(加害他人); 密谋;
indignities n. 侮辱; 轻蔑; 侮辱性的行为;
calf n. 腓; 小腿肚; 小牛; 牛犊; (象、鲸等的) 崽，幼兽;
snout n. (猪等动物的) 口鼻部，吻; (人的) 鼻子; 吻状突出物;
aquaplane v. 在潮湿路面上打滑失控; 滑水; n. 滑水板;
练习感悟：
