For Whom the Bell Tolls: confusing points

As our teacher told me, this is a tricky book to handle, but I didn't find it too hard to read. So far, I have finished around 80 pages of this book, and i found some tricky points of my book.

First, the biggest confusing point is that why the people in the cave always mentioned the train? Was it a action that have done by the enemies who wanted to capture all the troops who were trapped by them, or some thing else?

Second, how did those people meet each other(not including Robert Jordan who is the main character), and how could them gather enough people to blow up the bridge?

Third, where did the wife of Palbo come from, or what was her experience?

I mainly can under understand over 80% of the book, but these questions that I have show that i still need to improve my English reading skill.

"Ernest Hemingway" as My Oral Presentation Topic

      I choose "Ernest Hemingway" as my topic, because I am reading his book called "For Whom the Bell Tolls". 

      In addition, I also have done reading his another book called "Old Man and Sea". I found out that he is a fascinating author with lots of classical books, and i am trying to figure out how could he write such good books. 

      Therefore, this research will give me the back ground of him and help to understand the novel more efficiently and logically.

Link:

http://www.britannica.com.ez.sccd.ctc.edu:2048/EBchecked/topic/260825/Ernest-Hemingway

Publish Post

United Nations to appoint space ambassador to act as first contact for aliens visiting Earth

http://www.dailymail.co.uk/sciencetech/article-1315336/United-Nations-appoint-space-ambassador-act-contact-aliens-visiting-Earth.html?ito=feeds-newsxml

Summary: 

      Indeed, the more planets human find, the more likely human will connect to aliens directly or vicariously, and the astrophysicists will be the first group of human that connect to those aliens. In contrast, if once the aliens come to earth, they will probably turn the earth to their colony, as what American did to native Indians after them found the American continent. Therefore, it might be dangerous to human, if the connect between human and alien is established.

Personal perspectives:

      Aliens once were pretty fascinating to me, due to the curiosity of  their appearance and the way that how they will act. However, my opinion has been changed since I saw the movie which told a story of an invasion that would be done by those aliens. This article announced the same opinion as I have. The outer space is unknown, and human is interested about it. Thus, we try to connect to them. On the other hand, the result of the connection is ambiguous, which means that will probably cause a severe consequence, such as a war, or lead to a positive result.
     I think we should try to discover them first, after all, human is curious about it. However, we'd better not try to connect with them, unless we have a super strong confidence about the weapons that we have. Therefore, even curiosity is the main power to push us forward, we still need to consider our security first.

vocabulary:

1. mechanism: the atomic process that occurs during a chemical reaction

2. coordination: the skillful and effective interaction of movements

3. encounter: a minor short-term fight