He landed feet first.

他落地时双脚先着地。

《牛津词典》

Enter the water carefully and feet first.

小心入水，脚先入水。

youdao

Go in feet first so that you can know how deep the water is.

脚先入水，这样你就能知道水有多深。

youdao

At sixty degrees below zero, a man with wet feet must not fail in his first attempt to build a fire.

VOA: special.2010.05.01

Then he flung outward, feet first, with a swish, Kicking his way down through the air to the ground.

然后，纵身一跳，他两脚先伸出去，在空中乱踢乱舞，于是飕的一声，降落到地面。

耶鲁公开课 - 现代诗歌课程节选

back when America was first getting its feet and like, started to write its own literature.

那个时候的美国刚刚站稳脚跟准备创作自己的文学。

写作课程比较难 - SpeakingMax英语口语达人

That a proper, fundamental feet first slide would have left no doubt about the play.

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The third rule in dressing for the dangerously cold: Hands and feet first.

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Other firms with deep pockets, such as NEA and KPCB, seem to be cautiously dabbling, but not really jumping in feet first.

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