对风能和其他天然的太阳能来说，能量流异常稀薄的：化石燃料的浓缩度比太阳能高十到五十倍。

In terms of wind and raw solar energy, the flow is exceptionally diluted: solar is ten to fifty times less concentrated than fossil fuel.

youdao

六十位年龄在二十五到五十岁之间的身体健康的男性在六周之内，每天都食用了这种草本植物的提取物。

Sixty healthy men aged between 25 and 52 took an extract of the herb twice a day for six weeks.

youdao

这个男人的名字据说是“摩洛克”，他看起来有七十岁了，实际却只到五十，某些时间以外的东西加速了他的衰老。

The man's name was said to be Murlock. He was apparently seventy years old, actually about fifty.

youdao

They also found some stockpiles of the virus from the 1950s that they still had on an Army base in Maryland,I think.

政府也在马里兰军队驻地发现了,从十九世纪五十年代储存到现在的病毒

耶鲁公开课 - 生物医学工程探索课程节选

I would guess that probably 30% to 50% of you do this everyday, you put a piece of plastic, a synthetic piece of plastic into your eye to improve your vision.

我猜你们有百分之三十到百分之五十的人,每天会做这样的事,将一小片塑料,合成塑料放到眼睛里,来提高自己的视力

耶鲁公开课 - 生物医学工程探索课程节选

You can find a whole- you can sort of find a deep and abiding kind of American nationalism still in a lot of these budding Southern patriots, even by the 1850s, especially when they get scared about what secession might actually mean.

你会发现,可以说你会发现一种深层持久的,美国民族主义仍旧根植于许多,南方爱国者们心中,甚至到十九世纪五十年代还是如此,特别是当他们开始害怕,脱离联邦会导致何种不可预料的结果

耶鲁公开课 - 美国内战与重建课程节选