Ist or sind??

[urban girder]

You're thinking of "Sie" formal?

So that only works if you are talking directly to someone, not to someone else about them

du/Sie are both "you"

You're not telling her "You fell from your bike"

You're telling someone else "She fell from her bike."

Another clue, a little less obvious:

If it were the formal you "Sie", the possessive pronoun would also be capitalized

Sie sind von Ihrem Fahrrad gefallen! Warum haben Sie das nur getan?

Also, the whole usage of the name: if I told you, "LK fell from your bike"

Well, that doesn't make sense.

[dark comet]

Ahhh ofc that makes sense

Thank you