YOU SAID:
i am taking the plane to denmark
INTO JAPANESE
私はデンマーク行きの飛行機に乗ります
BACK INTO ENGLISH
I'm on a plane to Denmark
INTO JAPANESE
私はデンマーク行きの飛行機に乗っています
BACK INTO ENGLISH
I'm on a plane to Denmark
That didn't even make that much sense in English.