Many of them were using a pea-sized speaker to receive the answers over a radio frequency.

很多人借由一个豌豆大小的耳机来通过无线电频率接收答案。

youdao

Many of them were using a pea-sized speaker to receive the answers over a radio frequency.

很多人借由一个豌豆大小的耳机来通过无线电频率接收答案。

youdao