Definition
To comprehend or follow what someone is saying or explaining.
理解某人所说的话。
I'm explaining a bit fast, are you all with me?
我解释得有点快，你们都跟得上吗？
This concept is a bit complex; please let me know if you are not with me.
这个概念有点复杂；如果你没跟上请告诉我。
He used a lot of technical terms, I wasn't with him at all.
他用了很多专业术语，我完全跟不上他。