她在厨房里打翻了热汤，这是个意外。

She spilled hot soup in the kitchen—it was an ___accident.

这起事故导致两辆车严重损坏。

The ___accident caused serious damage to both cars.

他骑自行车时摔倒了，但幸运的是这只是个小意外。

He fell off his bike, but luckily it was just a small ___accident.