speed barrier的用法和样例：
例句
- The speed of light turns out to be nature's speed limit.
光速原来是自然界的速度极限。 - You see, the existence of a natural speed limit for the motion of any object, or the sending of any signal, makes simultaneity in our ordinary sense of the word lose its meaning.
你看，任何运动的物体或信号的发射都存在自然的速度极限，这使我们了解的词语的普通意思失去了意义。
