[1] Joshua Lionel Cowen，a New York inventor，was born in l 877．In 1 900，he created maybe the most popular Christmas toy of the last century —little electric trains that circle Christmas trees．More than 50 million Lionel train sets have been sold worldwide，and today Lionel produces more than 300 miles of track each year．
[2] Like many American inventors，Josh Cowen，who died in l965，was self-taught．According to history books．when he was 7 he carved a wooden toy train and tried to put a little steam engine on it．The engine blew up，but there were no complaints from his parents and eight brothers and sisters．
[3] As a 23-year-old working at an electric fan company，Cowen dreamed up putting a little battery—powered fan motor onto a wooden toy train he called the Electric Express．He took it to a toy store，and they put it in the window to replace a train you had to push around by hand．Within days，Christmas shoppers snapped up six Lionel trains, and the company business took off．
[4]While there were many toy train companies—the first electric train was exhibited at the 1893 World’s Fair in Chicago—Cowen’s invention beat them a11．probably because he tied it to Christmas and produced the toy villages and other things to put around the tree and the train．Still，competition has not stopped．Today there are many companies making toy trains of all sizes，some on tracks using electricity，some on the floor using wind-up springs(发条)．
[5] One of the best places in Washington to see a big toy train display is the U．S．Botanic Garden．The big glass building at the foot of the U．S．Capitol has a single train running in one room and a bunch of trains in another big room．____________________________ is one of the most popular holiday attractions in the city．
小题1:What does the author want to tell us about Joshua Lionel Cowen in Paragraph l?(no more than 8 words)
小题2:What was Cowen’s family’s attitude toward his devotion to invention?(no more than 6 words)
小题3:What made Cowen succeed at the 1893 World’s Fair?(no more than 8 words)
小题4:Explain the underlined sentence in Paragraph 3 in English．
小题5:Fill in the blanks in Paragraph 5 with proper words．(no more than 8 words)
4Y(g)＋Z(g)，ΔH<0，在某温度时
的浓度随时间变化的曲线：
后，反应就终止了