Theory:

     Among my goods, I chose a few valuable items and presented those to the kind king. In return, the king also gave me expensive presents. The ship stayed on the island for a few days. Meanwhile, I did good business and earned a lot of money.
 
     When it was time to leave, I went to meet the king. I thanked the king for his kindnesses and all the favours he had done to me. The king again gave me many valuable farewell gifts. Finally I returned to my city Baghdad as a rich man.
Explanation:
 
Sindbad took his bag, and it contained several valuable goods. From them, the sailor took a few precious things and presented them to the kind-hearted king. The kind king accepted his gift with immense pleasure, and in return, he expressed his love by offering some expensive items. The ship from "Baghdad" stayed on the same island for a few days. Within that short time, Sindbad earned a lot of money and succeeded in his business. This point shows his transformation from a poor to a rich person. When he arrived on the strange island, he had nothing in his hand. But when he decided to leave the island, he had a vast amount of wealth in his hands. In this way, Sindbad became rich again.
 
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King Mihrjan presented expensive gifts to Sindbad
 
Sindbad went to meet the king. It was his time to leave the island. Sindbad thanked the king for his generosity and the favours he had done for him. The king gave him many unique farewell gifts. At last, Sindbad returned to his city, 'Baghdad', as a wealthy man.
 
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King says goodbye to Sindbad
 
Meanings of the difficult words:
 
S.No
Words
Meanings
1
FarewellAn act of parting or of marking someone's departure
2
ExpensiveCosting a lot of money
3
GenerosityThe quality of being kind and generous
Reference:
State Council of Educational Research and Training (2019). Term-1 English Standard-7. Sindbad-My First Voyage (pp. 97-104). Published by the Tamil Nadu Textbook and Educational Services Corporation.