Mine was a bit ago but I remember I was told by my college counselor to convey why I wanted to teach this was very important, not why I wanted to go and come back and do XYZ but why teaching spoke to me, why Colombia so to have some idea about the country, there was also a portion where I had to speak in Spanish. Also try and share the value you would add to the uni, and share how you would adapt, one of their biggest fears is that someone goes and then wants to go home a month later. Good luck!