填空题

What does David R. Smith want to convey when he says "... except when they’re magic" in the last paragraph

【参考答案】

It seems impossible to build a cloak people wish to have．

<上一题目录下一题>

热门试题

填空题

majority→major

填空题

To make metamaterials work for all lights in the visible spectrum is rather difficult because of the limitation of ______.