@Switch Blayde
3. Never use a verb other than "said" to carry dialogue.
The line of dialogue belongs to the character; the verb is the writer sticking his nose in. But said is far less intrusive than grumbled, gasped, cautioned, lied. I once noticed Mary McCarthy ending a line of dialogue with "she asseverated," and had to stop reading to get the dictionary.
4. Never use an adverb to modify the verb "said" โฆ
. . . he admonished gravely. To use an adverb this way (or almost any way) is a mortal sin. The writer is now exposing himself in earnest, using a word that distracts and can interrupt the rhythm of the exchange. I have a character in one of my books tell how she used to write historical romances "full of rape and adverbs."
Both of these "rules" are situational.
In the midst of combat, a factory floor, a vehicle crash, or similarly loud environment, if a character merely "said" something, most other characters are unlikely to hear what was said.
In those situations, or those of high emotion, a character probably should shout, yell, etc.
Commanded I use on some occasions; the military attempts to teach Officers and NCOs a "Command Voice" but despite their rank, not everyone is capable, or at least not consistently. Law enforcement officers, or others in a position of authority may (try to) use this "voice" too.
Joe commented, "I don't know you anymore."
There are times a person says something and doesn't expect a reply. Most of us can tell by their tone. It can be difficult to determine that in writing, without using a descriptive, such as "Commented" IMHO it is even more intrusive to tell the speakers thoughts.
Muttered, is another variation of said that conveys a statement that may not have wanted a response, and also the volume of their utterance.
Whispered, or said quietly, is appropriate in circumstances where a character is attempting to be stealthy, or is in church during services, or a court room, when talking out loud would be problematic.
When I first started writing, long before I began posting on SoL, I used too many variants for said, just to "spice things up" but, as in cooking, one should probably use "spices" sparingly.
However, in situations where speaking in a conversational voice is problematic, then using another, more appropriate to the situation, descriptive word is what I prefer.
When the hapless recruit joined the formation late, and without his rifle, the Drill Sergeant, his face red, and spittle flying, said, "Where is your rifle recruit? Drop and give me twenty!"
Should a writer use said, or shout in the above situation?