语法填空

　　When a young man went through 　　1　　 desert, he came across a spring of clear and sweet water．He filled his leather container so that he could bring some back to an elder 　　2　　 had been his teacher．After a four-day journey, the young man 　　3　　(present)the water to the old man．His teacher took a deep drink, smiled 　　4　　(warm), and thanked his student very much for the sweet water．The young man went home 　　5　　 a happy heart．

　　After the student left, the teacher let 　　6　　 student taste the water．He spit out(吐出), 　　7　　(say)it was awful．Apparently, it was no long fresh because of the old leather container．He asked his teacher, “Sir, the water was awful．Why did you pretend to like 　　8　　?”

　　The teacher replied：“You tasted the water, 　　9　　 I trust the gift．The water was simply the container for an act of kindness and love．Nothing could be 　　10　　(sweet)．