“改善环境质量，建设美丽家园”是我们共同的责任，下列做法不利于保护环境的是（　　）

Now more and more workers ______their free time trying to improve themselves at school or college.

短文改错。文中共有10处语言错误，每句中最多有两处。每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：在错的词下面画一横线，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 Xiaohua,

    It is four days since mother recieves the operation. She is feeling much more better. The doctors told me the operation was successful, but because her old age she had to stay in hospital for other two weeks. The doctors also say it was quite necessary for him to do so. We expect to get a full report in two and three days. Please tell the good news to the rest of the family as soon as possible. You need't come here. I'm able to look at mother by myself. You can send some flower to her. She will feel very happily.

Yours,

Xiaohua