Read the following text to answer questions 19 to 22.

Once upon a time, there were two butterflies, Teri and Roni. They are friends. Teri and Roni had the same crown.

One day, Kodi a frog, saw Teri and Roni quarreling "You took it!" said Roni "No. I did not!" said Teri.

"Hey, what's the matter?" asked Kodi.

"Teri stole my crown!" said Roni.

"No. I didn't," said Teri.

"Yesterday, I still had my crown when she came to visit me," said Roni.

"Today I cannot find the crown! Look!, she is wearing it!" Roni shouted.

"My mom gave me this crown," Teri explained.

Kodi suggested they all go to Roni's house.

"Where did you put it?" said Kodi to Roni.

"I put it on the table," Roni answered.

They didn't find the crown.

"May be, it fell down." Kodi looked under the table. Nothing was there.

"It was my favourite crown!" Roni sobbed.

"I didn't steal yours, but if you like it so much, you can have mine," Teri gave Roni the crown.

"It's here!" Kodi saw the crown behind the curtain.

Roni stopped crying, "Thank God, Kodi found it!"

"Sorry, Teri, I accused you. I'm a terrible friend!"

"It's OK," said Teri. "Let's say thanks to Kodi!"

21. From the story, we can learn that ....