①三大改造建立起社会主义公有制  ②用普选的方式产生人民代表

③《共同纲领》是选举的法律依据  ④选举产生了各级人民代表大会

求方程x²+3x﹣1=0的解，除了用课本的方法外，也可以采用图象的方法：画出直线y=x+3和双曲线y=$\frac{1}{x}$的图象，则两图象交点的横坐标即为该方程

的图象，则两图象交点的横坐标即为该方程的解．类似地，可以判断方程x³+x﹣1=0的解的个数有____ 个．

    Can you write down a Chinese word being read to you? Sometimes it can be difficult when you find the word is not included in most dictionaries.

    Lu Jialei, 14, from Hangzhou Foreign Language School, won the CCTV Chinese Character (汉字) Spelling Contest on Oct 18^th, 2013. About 160 people competed. The host read a word to the contestant, explained its meaning and gave sample sentences. The contestant was required to write down the word.

    Winning the contest was a “surprise” to Lu. “I was not the smartest one,” she said. “But I paid attention to details.” To prepare for the contest, she and her teammates studied the Modern Chinese Dictionary for 10 days. There are more than 56,000 entries (词条) including characters, words and phrases in it. She also had a secret weapon. She studied how Chinese characters were formed.

    “When others paid attention to the plot of a story, she looked at how authors use words and sentences to express themselves,” said Su Yunsheng, Lu's Chinese teacher. Su is happy to see students like Lu find the beauty of Chinese language.

    “Besides using something Chinese and having Chinese traditional festivals, learning to write Chinese characters is also an important part of inheriting (传承) Chinese culture,” said Su.

成语堪称中华文化的“活化石”，是中华民族宝贵的文化遗产。为此，某班决定开展“精彩成语世界”综合性学习活动。请你参与并完成下列任务。