system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How do animators sync video and audio so fluidly?
gpt
It's easier than you think, with animation tools, you can play 1/30 a second of sound to know exactly what sound the voice actor is making, and draw based on that. With practice, you can do this very intuitively. Mimicking the words IRL helps with what mouth shapes you need to draw, and with most animation you dont need to be extremely accurate.

And in most cases, lip syncing is done after the voices have been recorded.