练习材料：

Lesson 7-2  Bats

Every solid objectwill reflect a sound, varying according to the size and nature of the object. Ashoal of fish will do this. So it is a comparatively simple step from locatingthe sea bottom to locating a shoal of fish. With experience, and with improvedapparatus, it is now possible not only to locate a shoal but to tell if it isherring, cod, or other well-known fish, by the pattern of its echo.

It has been foundthat certain bats emit squeaks and by receiving the echoes, they can locate andsteer clear of obstacles -- or locate flying insects on which they feed. Thisecho-location in bats is often compared with radar, the principle of which issimilar.

bæts

ˈɛvri ˈsɒlɪd ˈɒbʤɪktwɪl rɪˈflɛkt ə saʊnd, ˈveəriɪŋ əˈkɔːdɪŋ tuː ðə saɪz ænd ˈneɪʧər ɒv ði ˈɒbʤɪkt. əʃəʊl ɒv fɪʃ wɪl duː ðɪs. səʊ ɪt ɪz ə kəmˈpærətɪvli ˈsɪmpl stɛp frɒm ləʊˈkeɪtɪŋðə siː ˈbɒtəm tuː ləʊˈkeɪtɪŋ ə ʃəʊl ɒv fɪʃ. wɪð ɪksˈpɪərɪəns, ænd wɪð ɪmˈpruːvdˌæpəˈreɪtəs, ɪt ɪz naʊ ˈpɒsəbl nɒt ˈəʊnli tuː ləʊˈkeɪt ə ʃəʊl bʌt tuː tɛl ɪf ɪtɪz ˈhɛrɪŋ, kɒd, ɔːr ˈʌðə wɛl-nəʊn fɪʃ, baɪ ðə ˈpætən ɒv ɪts ˈɛkəʊ.

ɪt hæz biːn faʊndðæt ˈsɜːtn bæts ɪˈmɪt skwiːks ænd baɪ rɪˈsiːvɪŋ ði ˈɛkəʊz, ðeɪ kæn ləʊˈkeɪt ændstɪə klɪər ɒv ˈɒbstəklz -- ɔː ləʊˈkeɪt ˈflaɪɪŋ ˈɪnsɛkts ɒn wɪʧ ðeɪ fiːd. ðɪs ˈɛkəʊ-ləʊˈkeɪʃənɪn bæts ɪz ˈɒf(ə)n kəmˈpeəd wɪð ˈreɪdə, ðə ˈprɪnsəpl ɒv wɪʧ ɪz ˈsɪmɪlə.

任务配置：L0+L4

知识笔记：

单词：1、shoal：浅滩，a shoal of fish：一群鱼，2、comparatively：比较，相对，3、herring：鲱鱼，4、pattern：模式，图案，方式，5、squeaks：吱吱声，6、steer：引导，暗示，7、obstacle：障碍，障碍物，8、radar：雷达，9、principle：原理，原则，道理，信念

音标：

感悟：今天有点困，这篇文章又有点拗口，虽然比较短，但是读起来还是挺困难的，有打结的现象，不过总体来说表现还行，录了两遍勉强达标