The least and the fewest
- He went up the steps without showing the least anxiety.
- She had not the least idea of what was going on.
Before plural abstract nouns we can use the least of.
- ‘I think she is really upset with you.’ ‘That is the least of my worries.’
The fewest is the superlative of few. It is used before plural nouns.
- New cars tend to cause less air pollution.
- He earns less money than his wife.
- I have got fewer problems than I used to have.
Note that in an informal style less is quite common before plural nouns.
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