"She is coming inside."
Translation:Sie kommt herein.
Your german sentence only makes sense in a sexual way.
Kommen like in the english sentence describes a movement from one point to another (even when not both points are directly mentioned). Shes coming inside. She is moving from the outside of the building to the inside of the building, to create a sentence in german you would use herein. Drinnen describes something that is just inside. She is cooking inside. Sie kocht drinnen. Theres no movement involved and its somehow stationary, this would be described by drinnen.
It's like the difference between "She came to school" and "She came at school".
Good to know the difference! I bet my german friends would have laughed a lot had I said that then
Nothing; it’s a contradiction like e.g. “she is rising down” would be.
“Rise” means moving up, so you can’t rise down; to come means to move towards the speaker, so you can’t come away from the speaker, which is what the hin- prefix means.
After I have submitted my answer, I have received this:
You have a typo. Sie kommt hinein.
So, if this is a contradiction, should I report it?
I’ve taken care of it. Thanks for the comment!
(And in general: if you can submit a free-text report, that can be fairly helpful, but generic reports of the type “sentence is unnatural or has an error” are not since they don’t identify the problem.)
Can I say "Sie kommt herein her." using separable verb herkommen which also means "to come".