Here's how the tone is conveyed:
* Frustration: The repetition of "Does it dry up / like a raisin in the sun?" conveys the feeling of being stuck and frustrated by the inability to achieve a dream.
* Sadness: The imagery of a "syrupy sweet" dream turning "sour" or "stinking" evokes a sense of sadness and disappointment.
* Anger: While not explicitly stated, the poem's overall tone is one of simmering anger. The speaker is clearly frustrated and disillusioned, which hints at a deeper anger about the situation.
The poem's tone is also confrontational and challenging. Hughes forces the reader to confront the reality of deferred dreams and consider their potential consequences.
Ultimately, "Dream Deferred" is a powerful poem that captures the complex emotions of those who face persistent barriers to achieving their dreams.