公车上书失败后，康有为、梁启超创办《万国公报》，通过介绍资本主义国家的政治和经济情况，继续宣传维新变法。不久，他们联和朝中大臣在北京组织____ ，随后，他们又把《万国公报》改名为《____ 》，维新派政治团体形成了。

阅读短文，然后从方框中选出可以填入文中空白处的单词

teacher   but    old    learn    with    boring     basketball    history    musician

Mr. and Mrs. Cooper are Americans. But now they are in Beijing ____ their kids. This is their first time to China.     

Mr. Cooper is a  ____. He sings very well. Mrs. Cooper is a ____. Her daughter studies at her school. Mrs. Cooper likes Beijing Opera very much. She thinks she can learn about Chinese ____ and culture. So she often goes to see Beijing opera. ____ her daughter doesn’t think so. She likes comedy , and her favorite movie is Mr. Bean. Mr. Cooper doesn’t like movies. He thinks they are____. He likes sports. His favorite sport is ____ . He likes Yao Ming very much. 

The Coopers want to go to Pingyao, Shanxi. It is an ____ and nice place. They want to take photos there. They can also____to speak Chinese. They can have a good time in China.

综合与实践：制作无盖盒子

任务一：如图1，有一块矩形纸板，长是宽的2倍，要将其四角各剪去一个正方形，折成高为4cm，容积为616cm³的无盖长方体盒子（纸板厚度忽略不计）．

如图，在△ABC中，DE∥BC，分别交AB，AC于点D、E．若AD=3，DB=2，BC=6，则DE的长为____ .