Please check this video.
I understood for performative verbs, if we are doing something and, at the same time, we are saying it, we don’t need to use the present continuous tense. I am not sure I have it right.
For example, when I say, "I promise to do my homework," I am making the promise as I say this.
However, "promise" is not a stative verb, so we could say, "He is promising to do his homework."
Some sites say these are performative verbs, e.g. accept, acknowledge, advise, apologise, and warn, etc.
This site says,
Performative verbs: when you say a word you do the action the word
There is a group of verbs called "performative verbs". When you say
these words, you actually do the action of the verb. If I say, "I
apologise", by saying "apologise", I make my apology.
Compare this to a word like "run". If I say, "I run in the morning",
then "run" just represents an action. Actually running is a different
action. I cannot run just by saying "run".
What if I was running and saying, "I run," at the same time?
Does the performative principle apply to other verbs, such as "run" or "eat"?
Would the utterance, "I run," be grammatical if I was running while saying it?
when you say a word, you do the action the word describes
This is correct but insufficient: when suggests that the only requirement is that the saying and the action occur at the same time, irrespective of causation; but that does not describe performative verbs accurately.
If I say, “I apologise”, by saying “apologise”, I make my apology.
The word by is essential: it tells us that saying “I apologise” is the cause of the action. Or, better: saying it is the action; saying it constitutes the action.
When you say, I run, your utterance alone does not make you run. Running and saying I run are not the same action (saying I run is an action of saying, whereas running a marathon is not an action of saying). That is why run is no performative verb in this context.
If you can say I run without actually running, then it is no performative verb. This is the ‘negative’ test, which is quite reliable. You can’t say I promise without actually making a promise, which is why promise is a performative verb: the utterance and the action cannot be separated, because they are one.*
*) You can use verbs that are normally performative in a weird way, such that they are no longer performative; but that is exceptional.