短文改错

该文中共有十处错误,每句中最多有两处,错误涉及一个单词的增加、删除或修改。

增加：在缺词处加一个漏字符号(∧), 并在此符号下面写出该加的词。

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。

     When I was ten years old, I went to Yangzhou with two American. I became their guide.

First, we went to the Shouxi River. They wanted to look around the river by the boat. After

buy the tickets, we got into a boat. We went around seeing the beautiful sight. After that, we

went shopping. The sellers couldn't spoke English. Though it was very harder, I tried my best

listen to their words carefully and translate the sentences. They bought some little things with

their help. Next, we went to a small zoo but took some pictures. When we felt hunger, we

went out and had lunch. After lunch, we visited some old house and learned more about Chinese

history.

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在“用单摆测定重力加速度”的实验中：

①甲同学分别选用三种材料不同、直径2cm的实心球做实验，各组实验的测量数据如下表．若要计算当地的重力加速度，应选用第______组实验数据．

③丙、丁两同学合作测量重力加速度，测出一组数据．丙用T²-L图象法处理求得重力加速度为g_丙；丁用公式法T=2π