Fill in the blanks in the story 'The Farmer and his Sons'.

Here's the story with the blanks filled in based on the context:

There was once an old, dying farmer (1) who. Before he died he wanted to teach his three sons how to be good farmers. So he called them to his bedside and said, 'My boys, I have an important secret to tell you: there is a great treasure buried in the vineyard. Promise me that you will look for it when I am dead.'

The sons gave their promise and (2) then they began looking for the treasure. They worked very hard in the hot sun (3) digging. They pictured boxes of gold coins, diamond necklaces, and other such things.

(4) For days but they found not a single penny. They were very upset (5) at first. However, a few months later the grapes started to appear on the vines. Their grapes were the biggest and best in the neighbourhood and they sold them for a lot of money. Now the sons understood (6) what their father meant and they lived happily ever after.