Page 333 - Practical English Usage 3ed - Michael Swan, Oxford

5 least as adverb
Least can be used as an adverb (the opposite of most).
She always a"ives when you least expect it.
f don't much like housework, and I like cooking least ofall.
6 at least
At least means 'not less than (but perhaps more than)'. How old do you think he is? -At least thirty.
He's been in love at least eight times this year.
We can also use at least as a discourse marker (see 157) to suggest that one thing is certain or all right, even if everything else is unsatisfactory.
We lost everything in the fire. But at least nobody was hurt.
7 not in the least
We can use not in the least in a formal style to mean 'not at all', especially when talking about personal feelings and reactions.
f was not in the least upset by her bad temper. For less and fewer, see 320.
319 left
The past participle of leave - left - can be used in a special way, to mean 'remaining', 'not used', 'still there'.
What did you do with the money that was left? After the explosion, only two people were left alive.
Left is common after there is and have got.
There's nothing left in the fridge.
f haven't got any money left: can you get the tickets?
320 less and fewer
1 the difference
Less is the comparative of little (used especially before uncountable nouns). Fewer is the comparative offew (used before plural nouns). Compare:
I earn less money than a postman.
I've got fewer problems than f used to have.
Less is quite common before plural nouns, as well as uncountables, especially in an informal style. Some people consider this incorrect.
I've got less problems than I used to have.
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less and fewer 320
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