a) The listener.
1- The listener presence can be inferred from some clues such as: "sir", "forsooth", "to make your will quite clear to such an one", "will't please you rise", "will go together down, sir".
2- The listener is a silent one, however he is there so there's a sort of interaction between speaker and listener which can be discovered in the speaker's words.

b) The present situation.
The situation is important because it describes the Duke's feelings and attitudes in front of a specific behaviour of the Duchess. He pictures himself like a good-manners teacher and let the reader understand that after the event remembered the Duchess died.

c) The subject-manner.
1- Line 46 underlines the relationship between past and present time. As the speaker says "there she stands as if alive", the reader understands how past and present interact in the Duke's life. He can see her every time he wants - we know he has a painting of her - through pulling a curtain. 
2- In the poem the speaker reveals his temperament through words and actions. He can be delineated as a jealous and very possessive man who wants his wife at home and intends to mould her as he wish. He is a proud man and he is pretty conscious of his social status ("my gift of a nine-hundred-years old name").
3- The Duke sees himself as a sort of educator and he elevates to an higher level than the other men and things. He is quite sure about his manners and behaviours and feels more important than the Duchess.  

d) The language. 
1. anaphoric features: "'twas" (line 25); "will't" (line 47).
2. references to the situation in which the speaker and listener find themselves: "the company below" (line 48); "we'll go together down" (line 54).
3. direct address: "will't please you rise?" (line 47).
4. contracted forms: "who'd" (line 34); "we'll" (line 53).
5. pauses, signalled by dashes: "and if she let herself be lessoned so, ..." (line 39). 
6. fillers when searching for the expression: "I know not how" (line 32).

e) The tone.
The tone is determined by the speaker's character and his history. It is an harsh tone which conveys the idea of an aggressive speaker. The form chosen from the poet reveals the character's anger and his possessive attitude towards the Duchess (words like "stoop", "blame", "disgusts", "excuse", "commands"...). He finally reached his goal: he has his Duchess all for him