hot 最普通用词，指温度很高，往往有灼热、滚烫含义。
warm 通常指温度不太高，介于hot与cold之间，不太热也不太凉，给人以舒适感。
burning 暗示热源是火，多用于夸张，指像火烧一样热。
参考例句
1. Is this burning an eternal flame? 在燃烧的，是永恒的火焰吗？
2. What am I doing? Fighting! What am I? Brave warrior! ! What should I do? Burning ! Burning ! 我在干什么？战斗！！我是什么？勇敢的战士！！我该做什么？燃烧！燃烧！燃烧！
3. On the horizon, a huge cloud of dense smoke from the burning oil well stretched across the sky. 在地平线上，由油井燃烧形成的一大团浓厚的烟雾横过天空。扩展，延伸，延续。
英英解释
n.
1. the act of burning something
2. pain that feels hot as if it were on fire
3. a process in which a substance reacts with oxygen to give heat and light
4. execution by electricity
5. execution by fire
6. a form of torture in which cigarettes or cigars or other hot implements are used to burn the victim' adj.
1. producing or having a painfully hot sensation
2. intensely hot
3. characterized by intense emotion
4. lighted up by or as by fire or flame
5. of immediate import
6. consuming fuel; used in combination
