发信

wǒ fā xìn le cuī tā kuài lái

我发信了，催他快来。

I sent off letters, urging him to come at once.

fā xìn rén

发信人

addresser

yī dàn bèi jī huó sān chā shén jīng huì fā xìn tòng jué xìn hào

一旦被激活，三叉神经会发信痛觉信号。

Once activated, the trigeminal nerve transmits pain signals.