Hi Joao, I try to answer your question: hold on=endure or keep going in difficult circumstances. e.g.: "if only they could hold on a little longer" hold up=remain strong or vigorous. e.g.: "the dollar held up well against the yen" I hope it'll answer your question, good luck :)

They both have more than one meaning. But, by asking about them and differentiation, I guess you are looking at the time meaning: Hold on: Means when you wait for something. You might say it to someone else to ask them to wait, "Can you hold on for a sec" Hold up: Means the cause or reason behind a delay. You might say "Construction work is holding up traffic"

Very similar but I think "hold up" implies that the other person is doing something and for them to stop their current action. For "hold on" they might not be doing anything at all. Both generally mean to wait. "Hold up" example: Person A: I just bought this new drink. I'm going to try it! Person B: Hold up! You need some ice first. Person A: Thanks! "Hold on" example: Person A: Are you ready to go get dinner? Person B: Hold on, let me check my email first. Person A: Okay!

Creio q "Hold on" seria tipo "Calm down" é pra uma situação mais "apurada". Já o "Hold up" é pra uma mais suave mas com um ar de seriedade [emoji][emoji].