Help with ggplot2 and plotting 3 variables on one line graph (accelerometer data, problem in comments)

Hi all! I'm still learning R studio so forgive how little I know. I have a project with examining accelerometer data with 3 axes of information (the picture is just of one axis). As you can see, I've been able to make a line plot of one of the axes using the following code:

ggplot (data, aes(x = time elapsed, y = ? axis name) + geom_line(color = "navy")

However, I'm really new to using ggplot, as I got by with just using basic R functions in my stats class. Can any of you lovely people help me out with code that would allow me to plot 3 variables of data on one graph, all different colours to show differences easier? I've messaged my stats teacher and didn't seem to know how to help, which is why I've come to you.

Sorry if I've worded this weirdly, please let me know if you need anymore information.

Thank you so much in advance, this is going to help my research paper so much.

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