three words translation!thanks!

three words translation!thanks!
ttranslate field of discourse
tenor of discourse
mode of discourse
into chinese
field of discourse,mode of discourse ,tenor of discourse are three variables of british linguist Halliday's register theory!
i know the meaning of that!but just cant find the exactly professinal chinese for that!
FIELD OF DISCOURSE is the linguistic reflection of the purposive role of the language user,--the type of social activity the language user is engaged in doing in the situation in which the text has occurred..
TENOR OF DISCOURSE is the linguistic reflection of the personal relationships between speaker/writer and hearer/reader—called PERSONAL TENOR,and of what the user is trying to do with language for/to his or her addressee (s) -- called FUNCTIONAL TENOR.*
MODE OF DISCOURSE is the linguistic reflection of the relationship that the language user has to the medium of communication.
thanks help me to get the exact chinese definition!