You don't need to stop video every one second like for duolingo, you just record video with monosnap and then later you replay this video and take notes. Taking notes while doing duolingo lesson will increase the time of learning. For youtube videos there is similar process you convert video to gif using freeconvert then you convert gif to pdf using pdf24. Then you read video and take notes. You could burn subtitles using VLC. Duolingo lessons or italki are same process because stopping video every one second seems boring process.
Small example of pdf before writing notes

![](https://m.stacker.news/101231)

cryotosensei

AskSN

Are you into numerology?

When you learn chinese or japanese or german on duolingo the number learning are first lessons then such lessons stops same for example for learning at italki or youtube, you need to write notes and be back to copybook from time to time or you will lose such informations as simple as that. Also I prefer pyn in code (there is same for japanese) as these letters writing seems little complicated like wo hen mang instead of still drawing on copybook which increases learning time a lot.