VOA慢速英语:Verizon and Google Propose Rules of the Road for the Internet

while,however,but,yet区别

but是连词，表示（较强的）转折，连接两个句子时只用加逗号。例如：I love her, but she doesn't love me.

however是副词，也表示（较强的)转折,但连接两个句子时要用分号，而且在这个词后还要加逗号。例如：I love her; however, she doesn't love me.或者将两句子分开写。例如：I love her. However, she doesn't love me.

while作连词使用时，表示（较弱的）转折，连接两个句子时用逗号，但两个句子的主语不一样。例如:I like singing, while my sister likes dancing.

yet作连词使用时，也表示（较弱的）转折，连接两个句子时也用逗号，但两个句子的主语是一样的。例如：He has a good job, yet he never seems o have any money.

2.The new proposal calls for rules barring service providers from preventing users from sending and receiving legal information of any kind.

prevent from阻止, 防止

例句：My only idea was to prevent the woman from speaking.
      我唯一的想法就是不让那女人讲话。

      Cotton mittens will prevent the baby from scratching his own face.
      棉的连指手套使婴儿不会抓伤自己的脸。

bar from禁止(接近〔做〕…)

例句：The members voted to bar women from the club.
      会员表决不让妇女加入该俱乐部。

      After the member was caught cheating, he was barred from the club.
      那会员行骗被抓后, 被开除会籍。

3.Others oppose the creation of a "two-tiered" system on the Internet in which some content gets a fast lane and other content goes slowly.

in which介词+关系副词引导定语从句。

4.And not all networks reach the last mile to a customer's door.

not all部分否定

all，every，both，always等用于否定结构时不是全部被否定，而是表示其中的一部分被否定。而且英语多半将not置于谓语中。

例如：

All is not a gold that glitters.（即Not all that glitters is gold.）
闪闪发光物，未必尽黄金。

Every one cannot write novels.（即Not every one can write novels.）
不是所有的人都能写小说。

I don’t like both of the novels.（即I like only one of the two novels.）
这两本小说我不是都喜欢。