Answer: a- to define the other; b- to reveal the speaker; c- to control circumstances.
Step-by-step explanation: a- to define the other: in this case, the black speaker is defined by the language imposed onto him by the white man, yet , " he is not allowed" to define himself through his own language. b- to reveal the speaker: a black person will certainly be stigmatised by a white person when this hears a black man speak. c- to control circumsatances: a person needs to name his reality , and he will do so through his language. A black man is forced to name reality through the white man's language, which means he cannot control his own reality.