"The nurse looked into my right ear."

Translation: La flegisto rigardis en mian dekstran orelon.

[MuttFitness]

Why using -n here after en?

[BarbaraMorris]

I think it's because "into" implies motion.
https://www.duolingo.com/comment/9650731/When-to-use-the-n-ending

I'm still a very long way from knowing when to use -n after a preposition.

[JohnWathen]

I think without the -n the sentence would translate as "The nurse looked in my right ear." (in vs into) which could mean that the nurse his/herself was inside the ear while looking.

[rwhubert]

Shouldn't a female nurse be a flegistino, and a male nurse a flegisto?

[mihxal]

"Flegisto" is a nurse. It can be male or female.

[CharlesDanielChr]

Isn't "en" a preposition?

[Sa967St]

Yes, but you use the accusative with a preposition to express motion. It if were "looking at" you would use the nominative but since it's "looking into" you use the accusative.

[celtmax]

"En multaj aliaj lingvoj oni uzas la akuzativon, dativon, genitivon aŭ lokativon post prepozicioj. En Esperanto oni uzas post prepozicioj la nominativon, ne la akuzativon, krom por indiki direkton post »en«, »sur« ktp."

https://eo.wikipedia.org/wiki/Akuzativo