托福tpo23 section2 第二篇文章的第一题和第三题 我选的b和ad 答案是a和ab 感觉答案错了...谁来帮我

托福tpo23
section2 第二篇文章的第一题和第三题 我选的b和ad 答案是a和ab 感觉答案错了...
谁来帮我解释下= =

你说的是dolphin的那个文章吗?还是第四个?
dolphin的第一题：
原文：
Professor:We have been talking about how sea animals find their way underwater,how they navigate,and this brings up an interesting puzzle,and one I'm sure you'll all enjoy.I mean,everybody loves dolphins,right?
And dolphins,well,they actually produce two types of sounds.Uh,one being the vocalizations you are probably all familiar with,which they emit through their blowholes.But the one we are concerned with today is the rapid clicks that they use for echolocation,so they can sense what is around them.These sounds,it has been found,are produced in the air-filled nasal sacs of the dolphin.
And the puzzle is how does the click sounds get transmitted into the water?It's not as easy as it might seem.
选项：
A Parts of the dolphin anatomy that allow it to navigate
B Two different types of communication used by dolphins
这是听力最开始,这里提到了这节课的中心：an interesting puzzle,既是 the puzzle is how does the click sounds get transmitted into the water.首先,研究的对象是海豚navigate的方法,不是与其它海豚communicate的方法.其次,尽管教授提到了海豚有两种不同的发声办法,但是今天这节课的重点是第二种发声方法,即快速click造成的声音.而且在后来的讲课中你也发现,她解释的重点是海豚大脑的特殊构造如何工作,使得这种声音能够传输到水中.B是一个很有迷惑性的选项.
至于第三题,不是多选题,所以我不知道你要问的是哪个文章了.
（第三题的话答案原文中很明显：Well,turns out dolphins have a structure in their foreheads,just in front of their nasal sacs,called a melon.Now,the melon is kind of a large sac-like pouch,made up of fat tissue.And this fat tissue has some rather fascinating acoustical properties...）
再问： dolphin后面那一篇...讲screen dance的
再答： AUV我第一题和你错的一样一样的，我也没想明白为神马选A不选B... 第三题： 原文 Student: But ? um, I have never used a movie camera or edited film before. How will we learn everything we need to know to ? ? Professor: Oh, don't worry. The cameras you will be using are pretty simple to operate. And you'll get to play with the film-editing software several times before beginning your project. You'll also have the option of working with a student in the film department, someone who's familiar with the technology. But the choreography and the end result will be your responsibility of course. B He tells them that technical assistance is available if they need it. D He tells them that editing techniques are easy to learn. 题问的是教授怎样鼓励学生做作业，紧扣原文，他从未说editing techniques是容易学的，只提到摄影机是比较好用的，并且学生可以用软件先练练手。而后他特别提到他们可以求助电影学院的学生，因为他们 familiar with the technology， 这属于technical assistance 。