如图所示，两列简谐波分别沿x轴正方向和负方向传播，两波源分别位于x=－2×10-1 m和x=12×10-1 m处，两列波的波速均为v=0.4 m/s，两波源的振幅均为A=2 cm。
假定英语课上老师要求同桌之间交换修改作文，请你修改你同桌写的以下作文。文中共有10处语言错误，每句中最多有两处。每处错误仅涉及一个单词的
中国共产党打响武装反抗国民党反动统治第一枪的起义是: A．秋收起义 B．南昌起义 C．广州起义 D．北伐战争
“Made in China” has changed Many shoppers in the West still prize labels，boasting(吹嘘)a product was made in Italy without knowing that a growing number of Italian products come from fact
They had all children well looked after ____ their parents relieved(放心) A. making B. being made C. to make D. made
（2010·黑龙江省哈尔滨市，3，3分）下面句子中加点词语使用正确的一项是( ) A．周围高高低低的树木鳞次栉比，庄严肃穆的修道院就坐落在
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