根据句意和汉语提示，写出单词的正确形式。

某化学兴趣小组对教材中“测定空气里氧气含量”的实验（如图1）进行了大胆改进，设计图2，（选用容积为45mL的18×180mm的试管作反应容器）实验方案进行，收到了良好的效果．请你对比分析图1、图2实验，回答下列有关问题：

（1）图1实验中发生反应的符号表达式为____ ．

（2）图2实验的操作步骤如下：

①点燃酒精灯．

②撤去酒精灯，待试管冷却后松开弹簧夹．

③将少量红磷平装入试管中，将20mL的注射器活塞置于10mL刻度处，并按图2中所示的连接方式固定好，再将弹簧夹夹紧橡皮管．

④读取注射器活塞的数据．

你认为正确的实验操作顺序是　____ （填序号）．．

（3）图2实验中，注射器活塞将从10mL刻度处慢慢前移到约为____ mL刻度处才停止．

（4）对照图2实验，你认为图1实验有何不足之处？____ （回答一点即可）．

Every great achievement has been the result of years of dreaming. Even in early times, people could realize the  1 of dreams. If a person has a dream and works hard, he or she will find a way 2 bring it into success.

Children do not have  3  knowledge. However, they are natural dreamers. We should not  4  them. With their rich imagination, they will  5  with fantastic dreams. History is   6of examples. Many great men were dreamers when they were children. One such dreamer was Thomas Edison. He used to 7  ostracized(排斥) when he was in primary school, but his achievements were greater than  8   in his time.

 Teenagers and young people should also be  9to dream. They had big dreams and their dreams 10their lives and even the world. Steve Jobs and Bill Gates are the good examples. They  11   developed technology and brought great progress to humans besides making money for   12 .

 Older people should believe that it is never 13  late to dream. Colonel Saunders  14  KFC at the age of 67. Everyone has a chance to make dreams15 .