1.Bike helmet自行车头盔;单车头盔
It turns out he'd gone to the garage to get his bike helmet and found two helmets there.
原来他已经去了车库取他的自行车头盔,并且在那儿找到两个头盔 。
2.have a concussion 脑震荡
I think I might have a concussion.
我想我可能有脑震荡 。
3.black box黑匣子
At the highest level of abstraction, we can view the system as a single entity (complex whole), or black box.
在抽象的最高级别上,我们可以将系统视作一个单个实体(复杂整体),或黑盒 。