中文剧本：

一条名叫小黑的狗，在一个小镇上生活。小黑是一只非常聪明的狗，它的主人是一个老人。老人和小黑之间有着非常深厚的感情。

有一天，老人生病了，需要住院治疗。小黑感到非常难过，因为它知道自己的主人需要它的帮助。于是，小黑毅然决定离开家，去寻找能够治愈老人疾病的草药。

小黑在寻找草药的过程中，遇到了很多挑战和困难。但是，它并没有放弃，一直坚持着。最终，小黑找到了一种能够治愈老人疾病的草药。

小黑回到家，将草药交给了老人。老人经过服用草药，很快就恢复了健康。老人感激地抱着小黑，说：“小黑，你真是一只天才狗！你是我的救星，我的守护天使。”

英文剧本：

Title: The Mission of a Dog

Scene 1

A small town. We see a dog named Little Black living with an old man. They have a deep bond.

Little Black: (barks) Master, what's wrong? You don't look good.

Old man: I'm sick, Little Black. I need to go to the hospital.

Little Black: (whimpers) Don't worry, Master. I'll take care of you.

Scene 2

Little Black sets out on a journey to find a herb that can cure the old man's illness.

Little Black: (thinks) I have to find that herb. I won't let Master down.

Scene 3

Little Black faces many challenges and obstacles on the way, but he never gives up.

Little Black: (panting) I can't stop now. Master needs me.

Scene 4

Little Black finally finds the herb he's been looking for.

Little Black: (barks happily) I did it! Master will be okay now.

Scene 5

Little Black returns home and gives the herb to the old man.

Old man: (smiling) Little Black, you're a genius dog! You're my savior, my guardian angel.

Little Black: (wags tail) Woof! Woof! (translation: I'm just happy that you're okay, Master.)

End of the story.