Are there any scenes which you find difficult to write; action, romance, loss and tragedy, etc.?
Combat scenes have been very difficult for me when I switched to writing in English. They are the only ones I originally was more comfortable writing in my native language (French). I am not sure why. I learned to write them thanks to my roleplaying experience, and the help of fellow posters on the forum. Now they are more natural, but the shorter they are, the better. They are not favorites to write at all.
Any scene involving children characters are complicated for me too. My experience with children is limited and I have a hard time figuring out the right development for them. I have been pushing my boundaries though and in my upcoming Fantasy project, Clairvoyance Chronicles, a couple of children characters show up.