短文改错

假定英语课上老师要同学之间交换修改作文，请你修改你同学写的以下作文。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增加、删除或修改。

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：在错的词下面划一横线，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限一词。

2. 只允许修改10处，多者（从第11处）不计分。

Attention please, everyone. We accepted the weather forecast on the radio this morning that there will have a heavy rain tonight. Be sure shut the windows and doors until you leave your classrooms. The winter sports meet that we planned to hold on tomorrow will be put off. After it becomes fine, we'll make other announcement. We will have classes on Thursday as usually. Since it is cold tomorrow, please put on more clothes in time. Those who comes to school by bike don't keep your umbrella open while riding.

市场调查分为准备阶段、（）阶段、（）阶段。