in British English.

'I am absolutely knackered.'

'Knackered' means 'very tired'.

As it's an extreme adjective we

can say 'absolutely knackered'.

'I am worn out'.

We say 'worn out' when we're tired

because we were busy.

'I am spent.' When you have no more

energy you are 'spent'.

'I'm just completely done in.'

We can also say 'done in'

and this is an adjective phrase.

'Now excuse me because I am

going to conk out'

- and that is a phrasal verb

which means 'go to sleep'.

Good night!