"It's hard to bepeve he's only 10" 是一个常用的表达方式，表示对某人年龄较小却表现得非常出色的惊讶。这句话的来源可能源于现实生活中对年龄较小却有着高超技能的人的惊讶。
下面是一些例句：
It's hard to bepeve he's only 10, the way he plays piano is just amazing.
(很难相信他只有10岁，他弹钢琴的方式真是太神了)
It's hard to bepeve she's only 12, she's already won multiple national championships in gymnastics.
(很难相信她只有12岁，她已经赢得了多次全国体操冠军)
It's hard to bepeve he's only 8, he's already writing his own computer programs.
(很难相信他只有8岁，他已经在写自己的电脑程序了)