which of these skills do you use most comfortably? an ENFP would use Extraverted Intuition (Ne) and Introverted Feeling (Fi) most easily, an ENFJ would use Extraverted Feeling (Fe) and Introverted Intuition (Ni) most easily.
Ne: making connections, ideas, possibilties, figuring something out and then going backwards to figure it out consciously, rapidly understanding information at a rate that is lightyears of other people, making distinctions that protect you from overgeneralizing, adapting quickly to change, learning through reflection on information you have already gathered and making connections, comparing/contrasting certain ideas and ways of doing things, distinguishing the best aspects of both and combining them into a new way of thinking/doing that is better than both of the originals
Ni: knowing for certain what will be, studying for long hours and getting nothing to all of a sudden having an epiphony and having everything come together at once, finding the leverage points of information that determine everything, completely understanding every little aspect of something, dissecting something into a thousand pieces and having them all come together, having a sort of "brain orgasm" in which you attain massive amounts of information
Fe: understanding how others feel, taking on what others feel yourself (like crying in movies for example), making decisions based on emotions and people involved, wanting to take care of everyone and being a big happy family, putting others before yourself
Fi: rich fantasy, constant drive to create, having a strong intense moral code that is completely independent of those around you, having a sort of "internal flame" that drives you passionately to carry out your beliefs, being good with animals and small children, love of nature, appreciation/creation of art and music, gentle and calm until values are violated (at which point, watch the fuck out hahaha), knowing what you feel and why (Intrapersonal Intelligence), self reflection,
PS: I use all of them pretty well, but it has to do with which ones you use most naturally =). I am ENFP and have been using Ne and Fi pretty much since I was born. if you are honest with yourself, you will know your type based on the skills that you utilize