If the trial expires and you aren't ready to subscribe, several "Full & Free" legal alternatives offer similar features to Acrobat Pro DC:
Using pirated software violates copyright laws and Adobe's terms of service. Safe and Legal Ways to Use Adobe Acrobat If the trial expires and you aren't ready
Pirating software is a violation of copyright laws, which can lead to legal action. Lack of Updates: If the trial expires and you aren't ready
The only way to ensure your files and device are safe is to use official Adobe channels: Adobe Acrobat Reader (Free) If the trial expires and you aren't ready