zhōng / fēng / hòu / tā / huàn / shàng / le / shū / xiě / bù / néng / zhèng / ， / wú / fǎ / zhèng / cháng / xiě / zì / 。

中风后他患上了书写不能症，无法正常写字。

After suffering a stroke, he developed agraphia and could not write normally.