先通读下面的短文，掌握其大意，然后从A、B、C、D四个选项中选择可以填入空白处的最佳答案。
Once there was a man named Chulong in Thailand. One day he saw a beautiful 1 when he was walking in the park. He went near it quietly and caught (抓住) it.
" 2 do you catch me?" asked the bird.
"I want to make money," said Chulong.
"Nobody will 3 me because I'll lose my beauty when I'm not free." Then the beautiful bird turned into a common one.
Chulong was unhappy.
The bird said,“ 4 you set me free, I will tell you three simple but useful rules. I'm sure they will 5 you."
"But how can I trust (相信) 6 ? You may fly away," said Chulong.
"I won't," said the bird.
Chulong set the bird free, and it sat in a tree.
Now tell me the 7 ，said Chulong.
“OK,” said the bird. "The first rule is never trust everything others say. The second rule is never be unhappy about 8 you don't have. The third rule is never throw away (扔掉） what you have in your hand'
You silly bird "shouted Chulong ". Everyone knows these three rules. You cheated (欺骗）me.”
But the bird said,"Chulong， 9 all your actions today. You had me in your hand but you threw me away. You trusted all I said. And you are unhappy about not having me. Although the rules are simple you never 10 them ". After saying this the bird flew away.
