6．Some animals, for example, elephants and koalas, live on grass and 　　　　(树叶).

5．Camels can live quite a few days w　　　　 water and food in the desert.

4．His uncle went abroad five years a 　　　　.

3．Teenagers should be allowed to make decisions by t　　　　　 .

2．Lisa is such a shy girl that it’s hard for her to sing in p　　　　 .

　　 根据句意和提示完成单词，使句子语法正确，意义通顺。请将答案写在题后相应的横线上。

1．In the north of China, autumn is the best s　　　　 of a year.