Translation:The owl notices that there are two small mice near.
The dummy subject 'there' is frequently used in existential sentences, but it isn't strictly necessary here. IanWitham1's sentence is proper English.
I've listed a couple articles discussing the absence of the dummy subject in existential sentences, and provided some examples and history of this construction.
In order to not create another mini essay here, I'll just link to what I wrote in this discussion: https://forum.duolingo.com/comment/40926973.
Nearby is actually s better translation here and should also be accepted
The moderators do say to use the 'Report' button, but the options given currently are rather limited:
- My answer should not be accepted. - The Finnish sentence is unnatural or has an error. - Something else went wrong.
How about including "The English sentence is unnatural or has an error"?
I picked the last one in the hope it attracts some attention and that someone will have a look at these sentence discussion posts.