常见句型：
1、We're only fifteen years old and kindred spirits.
我们才十五岁而且有着年轻的心态。
2、Although he is only fifteen years old, he looks very mature.
虽然他只有十五岁，但是看起来很成熟。
3、She was fifteen years old when she accompanied her brother on this adventure.
艾米加入哥哥此次冒险旅程的时候，年仅十五岁。
