Theory:

     The alarm was spread. People came running with shovels and the hole was soon mended.
 
     They carried Peter home to his parents, and before long the whole town knew how he had saved their lives that night. To this day, they have never forgotten the brave little hero of Holland.
Explanation:
 
The man then realised the situation and recognised Peter's dedication towards saving Holland. Soon after, the alarm was raised, and the residents from all across the village arrived with shovels in hand to close the dike hole. They quickly fixed the hole and assisted Peter in returning home to his parents. And the news of the bravery of the little boy (Peter) quickly spread across the town, as they heard how the small boy had saved their lives the previous night. They all realised the fact that if Peter hadn't been there, or if he hadn't cared to stop the leak, their home may have been flooded and they would have even lost in their lives.
 
The lesson teaches us many things and we can a learn lot from Peter.
 
a. 'Self-help is the best aid,' since if Peter had gone to get something from someone during that dark night, the water leaking may have gotten so bad that the dike hole would have been submerged by the time he returned, and the problem would have gone worse.
 
a. Patriotism - We should be proud of supporting/helping our country in times of need, regardless of our age, power, or position.
 
c. Determination - We must be persistent in our determination to complete a task as intended.
 
d. Courage- Do not be scared to face difficulties, especially if it involves something important/emergency.
 
Peter's story was based on a true incident that took place in Holland many years ago. People in Holland have never forgotten Peter's valiant efforts, and he is still regarded as the brave little hero who saved Holland.
 
Meaning of difficult words:
  
S. No.
Words
Meaning
1.
MendTo fix the repair/damage
Reference:
State Council of Educational Research and Training (2018). English Standard-10. The Little Hero of Holland- Mary Mapes Dodge (pp. 183-185). Published by the Tamil Nadu Textbook and Educational Services Corporation