## Writing formal propositions

### Task number: 2782

First write the following propositions using quantifiers. Then negate them, and finally write the negated propositions informally, like the original propositions.

#### Variant 1

All natural numbers are even.

#### Variant 2

Every prime number is odd.

#### Variant 3

Some natural number is divisible by all primes.

#### Variant 4

Between \(n\) and \(2n\) we can always find some prime number.