1. are busy. "忙于做某事"一般用"be busy doing sth."，"be"动词必须与主语在人称和数上保持一致。

14、根据上下文和括号里的汉语提示，在下面短文的空白处写出正确的单词或词组。使短文意思完整，语句连贯。

　　 Most of us 1_______(忙于) talking about and using the Internet every day， but how many of us know the 2______(历史) of the Internet？ Many people are 3_______(感到惊奇) when they find that the Internet was set up in the 1960s. 4_______ (那时 )， computers were large and 5_______(贵的)。 Computer networks didn't work 6______ (好) .If there was 7_______(出故障) with one computer in the netr work， the whole network stopped， so a new network system had to be set up. It should be good enough to be used by many 8______(不同的) kinds of computers. If 9______(任何部分) of the network was not working， information could be sent through another part. 10______(用这种方法) computer network system would keep on working all the time……

　　 答案分析

10. opening.结合上下文，倒奶救火、救人。倒奶容易，但“开那么多奶瓶”确是不易。注意，这里的opening是动名词，作句子的真正主语。

9. lives.the lives of eight people意指“八条人命”。

8. reached.结合文意和语法结构，动词后是名词，显然要用一个以“r”打头的及物动词。

7. everywhere.前面句子主、谓、宾具全，结合后面的“used 320 pints of milk to stop the fire”，显然是用奶灭的火。用“everywhere”表明“到处都是奶”。

6. shouted.里面着了火，进门后“shout”更合情理。

5. pushed.后面是“door”，又要填一个以“p”打头的词，push the door(推门)搭配合理。

4. decided.依据前面的“thought”和后面的一系列动作。decide to do sth. 用于表示“决定做某事”。

3. thought.前面的must be 表示“推测”，所以用“thought”比较合理。