托福TPO49听力答案解析，供大家参考。
Conversation1
1.What are the speakers mainly discussing?
A.The student’s difficulties locating sources for a research project
B.The topic of the student’s research project
C.The student’s request to visit a particular part of the library
D.Procedures for requesting different editions of a book
答案：C
解析：
学生的第一句话“I need to get into special collections,in particular the british literature”，通过I need to表明意图是来看图书馆中关于英国文学的书籍。而之后的全文都在讨论学生没有教授的授权，是否能借阅这些书。所以答案选C。
2.Why is the student unable to use later editions or reproductions of a book he mentions?
A.The later editions contain errors.
B.Professor Gray specified the use of a particular edition.
C.The later editions must be requested from another library.
D.Reproductions typically omit the specific material he needs.
答案：D
解析：
通过工作人员的题问和学生的回答，我们能定位到这道题。考点即是师生之间的问答，而回答我们要重点记。 学生说他的project需要用到文献当中的注释，而这些注释并未在复制品中体现，都被clean up了(clean up相当于D选项中的omit忽视)。所以答案选D。
3.Why is the student reluctant to contact Professor Gray?
A.He already has disturbed her several times during her time away from campus.
B.He does not feel comfortable about asking her for another favor.
C.He does not know her e-mail address.
D.He wants to surprise her with a completed project.
答案：B
解析：
同上题一样，又是通过师生问答引出重要考点。学生说：我希望自已能搞定这件事而不是让教授帮我，因为之前的extra time已经是教授帮的一个大忙了。而现在我觉得skating on thin ice with her。这里的skate on thin ice with her的表达非常重要，我们一定要理解，正如我们中文所说的如履薄冰。试想一下，当教授已经帮了你一个忙而你却没做好的情况下，你再去请求她的第二次帮忙，这种时候是不是如履薄冰，胆战心惊，最好还是别去找她了，对不对?所以这个学生也是同样的心理，故答案选B(再求教授帮第二次忙，学生心里会不舒服)。
4.What does the woman imply about the rules regarding Special Collections?
A.The rules are unfair to the students.
B.The rules are in place to protect the books.
C.The rules are determined by the professors.
D.The rules have changed since the previous semester.
答案：B
解析：
Employee用这样的一句话“If we don't maintain our policies,they'll disintegrate”再次拒绝了学生，这里的policies(policy政策)等同于B选项中的rules规定。如果我们不维持我们的规定，这些文献都会损坏。所以这些规定就是用来保护这些文献书籍，故答案选B。
...
Lecture1 (Alaska)
1.What is the main purpose of the lecture?
A.To contrast how different kinds of thaw lakes grow
B.To explain why a new theory of thaw lakes is gaining acceptance
C.To explain how processes in permafrost lead to the formation of thaw lakes
D.To describe two competing theories about the growth of thaw lakes
答案：CD
解析：
C:What we call the active layer of permafrost,which melts in the summer and refreezes again in the winter.
D:There's been considerable research done to try to figure out what causes them to be shaped and oriented this way. What makes them grow this way?
从这些内容来看，整个Lecture都在围绕着融湖是如何形成的。并且文章中提出了两个不同的理论来论证。第一个理论将“分”作为融湖朝向的起因，而第二理论则认为是坍塌造成的。
2.The professor explains thaw lake formation as a cycle of events that occur repeatedly.Summarize this cycle, starting with the eventflled in below.
Drag your answer choices to spaces where they belong. To remove an answer choice, click on it
Answer Choices
a. Meltwater flows into cracks in permafrost..
b. Ice wedges inside permafrost completely melt..
c. Freezing water expands cracks in permafrost..
d. Ice in the active layer melts as temperatures rise..
e. Permafrost shrinks and cracks as temperatures drop..
答案：EDACB
解析：
此题注意听时间词，以及时间之后所发生的事情。描述的是一个循环过程。
3. What is the significance of the 'protective shelf' discussed by the professor?
A.It prevents the slumping of lake banks.
B.It shields the lake surface from strong winds.
C.It redirects the waves to lake banks that do not face the wind.
D.It allows the lakes to grow in the same direction as the wind blows.
答案：C
解析：
这里说了，protective shelf使得湖岸得到保护，将波浪转移到左右两边。
4. According to the thaw slumping model, which side of a thaw lake grows fastest?
A.The side where the bank is shortest
B.The side least exposed to wind
C.The side that is at the highest elevation
D.The side opposite the protective shelf
答案：A
解析：
通过lecture可以知道，短的那边比较容易被融化，掉入湖中，所以答案是A
5. What is the professor's opinion of the thaw slumping model?
A.He thinks it was urgently needed.
B.He is not convinced that it has a firm basis.
C.He thinks it would be better if it were simplified.
D.He does not think it is very different from the old model.
答案：B
解析：
此句中我们可以判断出老师是不确定的态度,认为这个理论还没被很好地论证过。
6. Replay: Why does the professor say this:
A.He wants some information from the students.
B.He thinks that the students may find an example helpful.
C.He realizes that he forgot to mention an important topic.
D.He wants to point out an important difference between frozen ground and dry ground.
答案：B
...
以上为托福TPO49听力答案解析资料，供大家参考。