留美老师带你每日说英文 第408期:X光是如何透射身体的

 　　台湾籍旅美老师今天交给我们的句子是：

　　Soft tissue, on the other hand, isn't as dense¹, and contains mostly lower atomic number elements, like carbon, hydrogen, and oxygen. So more of the X-rays penetrate² tissues like lungs and muscles, darkening the film.

　　相反的，软组织不是那么致密，大部分含有较低原子序数的元素，如碳、氢及氧。所以比较多的X-射线能穿透如肺及肌肉组织，使底片变得较黑。

1 dense   

a.密集的，稠密的，浓密的；密度大的

参考例句：

• The general ambushed his troops in the dense woods. 将军把部队埋伏在浓密的树林里。
• The path was completely covered by the dense foliage. 小路被树叶厚厚地盖了一层。

2 penetrate   

v.透(渗)入；刺入，刺穿；洞察，了解

参考例句：

• Western ideas penetrate slowly through the East.西方观念逐渐传入东方。
• The sunshine could not penetrate where the trees were thickest.阳光不能透入树木最浓密的地方。