Fetal limb long bone and foot length measured by ultrasound may serve as useful reference in evaluating fetal growth.

结论胎儿四肢长骨及足长的长度与孕龄呈正相关，超声测量二者可评价胎儿发育情况。

youdao

This receiver requires an antenna and ground. The ground connection can be made to a water pipe (NOT a gas pipe!). The antenna can be a 50 foot length of wire stretched outdoors between two objects.

此接收机需要天线和地线，地线可以为金属水管(不能是煤气管)，天线可以是50英尺的线挂在两个物体上。

youdao

Now I didn't use--no hands-- that was just the notes that are naturally on the twelve and a half-foot length of vibrating air.

我没有用手控制,都是十二个半英尺高的震动空气柱,自然产生的音符

耶鲁公开课 - 聆听音乐课程节选

A gig is 10 to the 9, so it does two operations in the length of time it takes light to get from one foot off the table down to the table. That's amazing.

因此光行进一英尺的,时间内电脑可以,进行两次基本运算,这太神奇了。

麻省理工公开课 - 计算机科学及编程导论课程节选

Just answering the door, with her thirty-foot length of oxygen tubing trailing after her, had left her winded.

NEWYORKER: Letting Go

Named Yrvind Ten after its 10 foot length, the miniature vessel will be just 1.8 meters wide with two six meter-tall masts.

CNN: November 29, 2012 -- Updated 0332 GMT (1132 HKT)

One night in early autumn, with the swampy ground of the Nature Preserve papered with fallen leaves, I was hunkered down to examine a dead snake about a foot in length whose color I thought might in life have been green, when, as I stood, I felt something brush the top of my head.

NEWYORKER: Wakefield