Question 1

What does "let alone" mean?

Accepted Answer

Used to emphasize that something is even less likely or possible than something already mentioned.

Question 2

How do you use "let alone" in a sentence?

Accepted Answer

I can't afford a car, let alone a holiday.

Question 3

Is "let alone" formal or informal?

Accepted Answer

"let alone" is register-neutral — appropriate in both casual and formal contexts. Used to intensify a negative statement.