1、impulsive

If someone is impulsive, it means that they act on instinct, without thinking decisions through. If you worked for an entire year to save money for a car and then suddenly decided to spend it all on an outfit instead, that would be an impulsive purchase.

Impulses are short, quick feelings, and if someone is in the habit of acting on them, they're impulsive. When stores stock chocolate at the checkout line, they are hoping you will impulsively decide to buy it. When you call the person you have a crush on after promising yourself all day to maintain an air of dignified reserve, that's impulsive behavior. We might also call impulsive behavior whimsical or capricious.

Primary Meanings of?impulsive：

1.adj?without forethought

2.adj?having the power of driving or impelling

Usage Examples：

Still, the announcement would have to wait because “I wanted to give myself enough time to make sure it wasn’t an impulsive decision.”

Washington PostOct 28, 2015

2、audacious

This adjective is very bold — if you are audacious, you are daring and unconventional!

The adjective audacious comes from the Latin word audacia and means "daring, boldness, courage," and often gets applied in situations where someone does something pretty unusual, like becoming an astronaut and going to the moon. It can also mean challenging conventions and doing things that most people don't do, such as when Elizabeth Blackwell became the first woman in the United States to become a doctor. Blackwell then inspired Elizabeth Garrett Anderson to become the first female doctor in England. And the rest is history!

Definitions of?audacious:

1.adj disposed to venture or take risks

adj unrestrained by convention or propriety

adj invulnerable to fear or intimidation

Usage Examples:

And what would happen if US authorities attempted to carry out Mr Trump's audacious plan? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ??BBC Nov 11, 2015

Everyone returns to the audacious electric car company at the forefront of the battery revolution. ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? The Guardian Nov 4, 2015