Such signals would be brief and rare, but they would also be strong and unmistakable.

这种信号简洁明了，但准确性极强，不容易被弄错。

youdao

Such signals would be brief and rare, but they would also be strong and unmistakable.

这种信号简洁明了，但准确性极强，不容易被弄错。

youdao