temerarious

The hiker's temerarious leap across the icy gap stunned the whole group.

这位徒步者跨越结冰裂缝的鲁莽一跳，让整个队伍都惊呆了。

It was temerarious of the teenager to challenge the champion to a race.

那个少年向冠军挑战赛跑，真是鲁莽大胆。

They called his temerarious proposal to invest all savings in one stock unwise.

他们认为他把全部积蓄投进一只股票的这个鲁莽提议很不明智。