- If you can count them or assign a number to them, MANY and FEWER are correct.
- If you can’t reasonably count them, use MUCH and LESS.
This salad has too much dressing, and too many carrots. How much dressing did you put on? How many carrots did you add?
You couldn’t reasonably count the number drops of dressing added, use much. However, you could say, “How many teaspoons of dressing did you add?” because the number of teaspoons can be counted. You can, and probably did count the carrots; the use of many is appropriate.
You could say, “This salad has too little dressing.” Little, like much, is non-countable.
The movie had too few/many big-name stars [quantifiable], and I wish it more/less nudity [unquantifiable].
This register is for ten items or fewer.
In dialog, using these words improperly is acceptable if your intent is to present the character as someone of lower education or class, as is the use of other misapplied verbiage. That’s a topic for another post.
If you can remember these few constructs and play them in your mind as you’re writing—or speaking, for that matter—you should get it right 99.9% of the time. Where’s the other 0.1%? Somewhere out there the English language has an idiom that is the exception. It always does.
Feel free to comment when you find it.