下列各句中，没有语病的一句是(     )

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处起）不计分。

    I have been feeling tired these days and often find hard to concentrate on my study. My teacher told me that it was the sign of anxiety. She advised me to read an article about reducing tension and improving brain efficient. I listened to her and found some useful ways in it. I began to form a habit of taking a nap for 15minutes at noon and try to spare 30 minutes a day to get move. A walk on the playground was beneficial. Besides, following the author's advices, I would play words with friends during class break, which made the brain refreshed and worked better. Having fun with friends is really a good way of becoming relaxed.

    Being tired may influence our mood though it has positive side. The brain can be the more creative. The author reminds what we should not fall asleep with brush in hand and we had better do something creative.

 复习课上，老师要求学生用不同的方法鉴别稀硫酸和氢氧化钠溶液，小东、小南两位同学取同一溶液分别进行如下实验：

听第二段对话，回答下面3小题。