听力原文：
Recording Two 

In last week's lecture, we discussed the characteristics of the newly born offspring of several mammals. You probably remember that human infants are less developed physically than other mammals of the same age. But in today's lecture, we'll look at three very interesting studies that hint at surprising abilities of human babies.
In the first study, three-year-olds watch two videos shown side by side. Each featuring a different researcher, one of whom they'd met once two years earlier. The children spend longer watching the video showing the researcher they hadn't met. This is consistent with young children's usual tendency to look longer at things that aren't familiar. And really this is amazing. It suggests the children remember the researcher they've met just one time when they were only one-year-olds. Of course, as most of us forget memories from our first few years as we grow older, this early long-turn memories will likely be lost in subsequent years.
Our second study is about music, for this study researchers play music to babies through speakers located on either side of a human face. They waited until the babies got bored and inverted their gaze from the face. And then they change the mood in the music either from sad to happy or the other way around. This mood switch made no difference to the three-month-olds; but for the nine-month-olds, it was enough to renew their interest and they started looking again in the direction of the face. This suggests that babies of that age can tell the difference between a happy melody and a sad tune. 
Our final study is from 1980, but it's still relevant today. In fact, it's one of the most famous pieces of research about infant emotion ever published. The study involved ordinary adults watching video clips of babies nine months or younger. In the video clips, the babies made various facial expressions in response to real life events including playful interactions and painful ones. The adult observers were able to reliably discern an assortment of emotions on the babies faces. These emotions included interest, joy, surprise, sadness, anger, disgust, contempt, and fear.
Next week, we'll be looking at this last study more closely. In fact, we will be viewing some of the video clips from that study. And together, see how well we do in discerning the babies' emotions.
Questions 19 to 21 are based on the recording you have just heard.

Q19：What are the three interesting studies about?

本题问这三个研究是关于什么的。录音开头只是说 “人类婴儿的身体发育程度比同龄的其他哺乳动物要低” ，并未提及二者的相似之处，故排除选项A。选项B、C文中并未提及，也排除。选项D与文中提到的 “它们暗示了人类婴儿有惊人的能力”相符，故为正确选项。

听力原文：
Recording Two 

In last week's lecture, we discussed the characteristics of the newly born offspring of several mammals. You probably remember that human infants are less developed physically than other mammals of the same age. But in today's lecture, we'll look at three very interesting studies that hint at surprising abilities of human babies.
In the first study, three-year-olds watch two videos shown side by side. Each featuring a different researcher, one of whom they'd met once two years earlier. The children spend longer watching the video showing the researcher they hadn't met. This is consistent with young children's usual tendency to look longer at things that aren't familiar. And really this is amazing. It suggests the children remember the researcher they've met just one time when they were only one-year-olds. Of course, as most of us forget memories from our first few years as we grow older, this early long-turn memories will likely be lost in subsequent years.
Our second study is about music, for this study researchers play music to babies through speakers located on either side of a human face. They waited until the babies got bored and inverted their gaze from the face. And then they change the mood in the music either from sad to happy or the other way around. This mood switch made no difference to the three-month-olds; but for the nine-month-olds, it was enough to renew their interest and they started looking again in the direction of the face. This suggests that babies of that age can tell the difference between a happy melody and a sad tune. 
Our final study is from 1980, but it's still relevant today. In fact, it's one of the most famous pieces of research about infant emotion ever published. The study involved ordinary adults watching video clips of babies nine months or younger. In the video clips, the babies made various facial expressions in response to real life events including playful interactions and painful ones. The adult observers were able to reliably discern an assortment of emotions on the babies faces. These emotions included interest, joy, surprise, sadness, anger, disgust, contempt, and fear.
Next week, we'll be looking at this last study more closely. In fact, we will be viewing some of the video clips from that study. And together, see how well we do in discerning the babies' emotions.
Questions 19 to 21 are based on the recording you have just heard.

Q20：What does the second study find about nine-month-old babies?

本题问第二项研究对九个月大的婴儿有何发现。录音中提到第二项研究和音乐有关，研究中的实验表 “九个月大的婴儿能够区分快乐的旋律和悲伤的曲调” ，故选项A正确。其余三项录音中均未提及，故排除。

听力原文：
Recording Two 

In last week's lecture, we discussed the characteristics of the newly born offspring of several mammals. You probably remember that human infants are less developed physically than other mammals of the same age. But in today's lecture, we'll look at three very interesting studies that hint at surprising abilities of human babies.
In the first study, three-year-olds watch two videos shown side by side. Each featuring a different researcher, one of whom they'd met once two years earlier. The children spend longer watching the video showing the researcher they hadn't met. This is consistent with young children's usual tendency to look longer at things that aren't familiar. And really this is amazing. It suggests the children remember the researcher they've met just one time when they were only one-year-olds. Of course, as most of us forget memories from our first few years as we grow older, this early long-turn memories will likely be lost in subsequent years.
Our second study is about music, for this study researchers play music to babies through speakers located on either side of a human face. They waited until the babies got bored and inverted their gaze from the face. And then they change the mood in the music either from sad to happy or the other way around. This mood switch made no difference to the three-month-olds; but for the nine-month-olds, it was enough to renew their interest and they started looking again in the direction of the face. This suggests that babies of that age can tell the difference between a happy melody and a sad tune. 
Our final study is from 1980, but it's still relevant today. In fact, it's one of the most famous pieces of research about infant emotion ever published. The study involved ordinary adults watching video clips of babies nine months or younger. In the video clips, the babies made various facial expressions in response to real life events including playful interactions and painful ones. The adult observers were able to reliably discern an assortment of emotions on the babies faces. These emotions included interest, joy, surprise, sadness, anger, disgust, contempt, and fear.
Next week, we'll be looking at this last study more closely. In fact, we will be viewing some of the video clips from that study. And together, see how well we do in discerning the babies' emotions.
Questions 19 to 21 are based on the recording you have just heard.

Q21：What is the 1980 study about?

本题问1980年的研究和什么有关。根据录音内容可知，两1980年的研究 “是迄今发表的关于婴儿情绪最著名的研究之一” ，选项B与此介绍一致，故正确。录音中提到在视频中，婴儿对现实生活中的事件做出了各种面部表情，但该研究是通过这些表情分辨情绪的，故排除选项A。其余两项内容均未提及，故排除。