Tā xiǎoxiǎo niánjì jiù néng jiānchíbùxiè, nánnéngkěguì.
For someone so young to persevere is admirable and rare.
Tips
history
From Su Shi's 《荀卿论》 (Song): 子路之勇，子贡之辩，冉有之智…皆天下之所谓难能而可贵者 - the courage of Zilu, eloquence of Zigong, wisdom of Ran You: qualities 'hard to attain, therefore precious'.
usage
Always praising - stresses that the quality or act is hard to achieve, which is why it's valued. Often follows a description: 'X is Y - 难能可贵'.
