阅读理解

     Living in the foreign culture can be exciting, but it can also be confusing. A group of Americans who taught English in other countries recently discussed their experiences. They discussed that miscommunications were always possible, even over something as simple as “yes”and“no”.
     On her first day in Micronesia, an island in the Pacific, Lisa thought the waitress wasn't paying any attention to her. The day was hot she went into a store and asked, "Do you have any cold drinks?" The woman there didn't say anything. Lisa repeated the question again. Still the woman said nothing. She later learned that the woman had answered her: She has raised her eyebrows, which in Micronesia, it means, "yes".
     Jan remembered an experience she had in Bulgaria, a country in Europe. She went to a restaurant that was known for its cabbage. She asked the writer,“Do you have cabbage today?”He nodded his head. Jan waited, but the cabbage never came. In that country, a nod means "no".
     Tom had a similar problem when he arrived in India. After explaining something in class, he asked his students if they understood. They answered with different nods and shakes of heads. He thought some people hadn't understood, so he explained again. When he asked again, they did the same thing. He soon found out that his students did understand. In India, people nod and shake heads in different ways. It depends on where they come from.

增加：在缺词处加一个漏字符号（∧），并在其下面写出该加的词。

删除：把多余的词用斜线（\）划掉。

修改：在错的词下划一横线，并在该词下面写出修改后的词。

注意：1）每处错误及其修改均仅限一词；

2）只允许修改10处，多者（从第11处起）不计分。

Dear Tom,

    I'm happy to get from your letter and knew you're coming to China.

    Among the two trips to the Yangtze River and Mount Tai, both are high recommended (推荐). Personally, I prefer the tour along the Yangtze, longest river and one of the mother river of Chinese civilization. You can learn a tot about the history of China and Chinese people. Moreover, the scenery along the river are amazing, with many well-know sightseeing spots. That's because I think the trip along the Yangtze will be a better choice.

    I hope your suggestion will be of some help and you'll have a good time in China.

Yours,

Li Hua

已知关于x的方程x²+2x+m=0的有两个相等的实数根，则m为（  ）