help acrobat DC I can't see the letter.

Hello 황현준

As per the description above, you are getting a Blank PDF page in Adobe Reader DC, Is that correct? Please refer and try the steps from the following KB doc which discusses the similar issue: Reader DC show's only white page

PDF Files open blank on Mac

PDF opens as a blank page in browser with Acrobat or Reader 10.1.2

If the issue persists, please check for the latest update of Reader from Help>Check for updates. You may also repair the installation files of Reader from Help>Repair installation.

Let us know how it goes.

Regards,

Anand Sri.