1. They also had undetectable leels of virus in the brain and low leels in the spleen. 而对病毒在脑的水平及在脾中的低水平表达时他们也不能检测。
2. Nature lovers can revel in the undetectable webcasting of bats, sharks, and penguins at various sites around the world. 爱好自然的人可以在全球的网站上尽情欣赏悄悄从旁拍摄的蝙蝠、鲨鱼和企鹅等。
3. In these periods of darkness, undetectable to the human eye, sensors are able to pick up light coming from outside the device. 人眼无法觉察这些黑暗的间隙，但是光学传感器却可以捕捉从外界透射进来的光线。
英英解释
adj.
1. not easily seen
2. barely able to be perceived
