He's known for his impulsive spending, often buying things he doesn't need.

impulsive 是由名词 impulse（冲动）加上形容词后缀 -ive 构成的形容词，表示"冲动的、易冲动的"。impulse 来自拉丁语，本意是"推动力"，引申为"突然的冲动"。 impulsive spending 指未经深思熟虑、一时冲动进行的消费行为。