练习材料：
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.
ðɪs ɪz nɒt ˈiːzi, ænd meɪ rɪˈkwaɪə tuː ˈpɔːpəsɪz ˈwɜːkɪŋ təˈgɛðə. ɪn əˈnʌðə geɪm, æz ðə ˈtɜːtl swɪmz əˈkrɒs ði oceanarium, ðə fɜːst ˈpɔːpəs swuːps daʊn frɒm əˈbʌv ænd bʌts hɪz ʃɛl wɪð hɪz ˈbɛli. ðɪs nɒks ðə ˈtɜːtl daʊn ˈsɛvrəl fiːt. hiː nəʊ ˈsuːnə rɪˈkʌvəz hɪz ˌiːkwɪˈlɪbrɪəm ðæn ðə nɛkst ˈpɔːpəs kʌmz əˈlɒŋ ænd hɪts hɪm əˈnʌðə kræk. ɪˈvɛnʧəli ðə ˈtɜːtl hæz biːn ˈbjuːtɪd ɔːl ðə weɪ daʊn tuː ðə flɔːr ɒv ðə tæŋk. hiː ɪz naʊ ˈsætɪsfaɪd ˈmɪəli tuː traɪ tuː stænd ʌp, bʌt æz suːn æz hiː dʌz səʊ ə ˈpɔːpəs nɒks hɪm flæt. ðə ˈtɜːtl æt lɑːst gɪvz ʌp baɪ ˈpʊlɪŋ hɪz fiːt ˈʌndə hɪz ʃɛl ænd ðə geɪm ɪz ˈəʊvə.
这并非易事，可能需要两只海豚合伙干才行。在另一场游戏中，当海龟游过水族馆时，第一只海豚从上方猛扑下去，用腹部撞击龟壳。这一下子把海龟撞下去好几英尺。海龟刚恢复平衡，第二只海豚又冲过来猛击一下。这只海龟最终被撞到池底。此时的海龟，只要能站起来就满足了，但它刚站起来，就被一只海豚击倒。海龟终于屈服了，将4条腿缩进壳内。游戏到此结束。
任务配置：L0、L3、L4
知识笔记：
单词与短语
has been butted all the way down to 最终被撞到...
练习感悟：恢复行动力。
