negligent

The fire was started by a negligent smoker.火灾是有人随便吸烟引起的。

negligent parents粗心大意的父母

He was negligent in not reporting the accident to the police.他一时疏忽，没把事故报告给警方。

She was negligent about sending a thank-you note. [=she neglected to send a thank-you note]她一时疏忽忘记写感谢信了。