B　[细节理解题。由第四段的"Adams tried to make toys，masks，and rain boots out of chicle，but none of his products were commercially successful."可知，在制作口香糖之前，Thomas Adams制造了几种产品，但都不受市场欢迎。]

　　3．What was William White's contribution to chewing gum?

　　A．He added flavor to chewing gum.

　　B．He made a chewing gum machine.

　　C．He made chewing gum with chicle.

　　D．He made chewing gum hold flavor.

　　D　[细节理解题。由倒数第二段可知，William White在口香糖中加了糖、玉米糖浆和薄荷，因此使口香糖的味道可以持久。]

　　4．What is the text mainly about?

　　A．The history of chewing gum.

　　B．The benefits of chewing gum.

　　C．Different kinds of chewing gum.

　　D．The invention of the chewing gum machine.

　　A　[主旨大意题。综观全文可知，文章介绍口香糖的发明和发展历史。]

　　III.完形填空

There were about fifteen of us drawing and writing with chalk(粉笔) to spread hopeful messages in front of a railway station.We 1 with only about ten adventurers but as the momentum (动力) 2 ，we gained more energy，creative inspiration，and people.In the beginning，many people stopped 3 because they were curious about our actions.Later when we went on to chalk up some 4 colors and phrases on the floor，more people came over to see what we were 5 doing.I wrote on the floor，"Hope：there is nothing stopping you."