speak to

1. 提及

We haven't much time, please speak to the subject.

我们时间不多, 请不要离开话题。

speak up

1. 响亮地说

2. 公开发表意见; 畅所欲言

Uncle George spoke up in the prayer meeting.

乔治叔叔在祈祷会中发表个人意见。

She spoke up in defense of her political beliefs.

她为她的政见力辩。

to speak of

1. 值得一提的

It is nothing to speak of.

那不值得一提。