说 (shuō)
This word is used for both the act of speaking and the ability to speak.
Here are some examples:
* 你说什么？ (nǐ shuō shénme?) - What are you saying?
* 他会说英语。 (tā huì shuō yīngyǔ.) - He can speak English.
* 她正在说话。 (tā zhèngzài shuōhuà.) - She is speaking.
There are also other words that can be used for "speak" depending on the context, such as:
* 谈 (tán) - to talk, to discuss
* 讲 (jiǎng) - to tell, to explain
* 讲 (jiāng) - to speak, to talk (more formal)
It's important to note that the specific word used will depend on the context and the nuance you want to convey.