In Jackie Chan's time, martial arts practitioners didn't pay much attention to cultural lessons (in fact, there were hardly any), and they could only recognize one word. Jackie Chan's handwriting doesn't mean that he can't write a word. Maybe it's because he received too little culture and education since he was a child, his handwriting is poor, and there are many typos. It's better not to lose face. If you want to write, ask your assistant to write and sign your name yourself.
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