The secondary outcome measure was FFD (Finger-floor distance).

次要测量指标FFD（指地距）。

youdao

Police said the man apparently fired at the 11-storey building, which was completed last October, from a window on the third floor of his house, a distance of roughly 50 m (164 ft).

当地警方表示，遭到枪击的那幢11层高的公寓楼是于去年10月份时正式竣工的，这名男子是站在自己所住房屋第3层的窗户里向对面大楼射击的，两者之间的距离约为50米左右。

youdao

Try it. Measure the distance from the tip of your head to the floor.

测量一下你们的身高，再用身高除以你们肚脐到地面的距离。

youdao

Back at his apartment, on the third floor of an old brick building within walking distance of campus, techno music suddenly blared, startling his downstairs neighbors, who knocked on his door and called police to complain.

WSJ: Shooting Suspect's Behavior Provided Few Clues

She got down on the floor, spread her arms, stood up, stepped back to gaze from a distance, returned close up.

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The emirate is big on hype, but the view from his 45th-floor office bears out the boast: all swooshing highways, gleaming buildings and bustling ports in the distance.

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