illness/sick

Illness is a noun; sick is an adjective. There is no difference in the meanings of your sentences. 'Off sick' is rather informal.

Hi,

She had five days off work due to illness.

She had five days off sick.

Could you tell me what is the difference in the meaning between these sentences in regard to "illness" and "sick"?

There is not much difference. #1 sounds more formal, but #2 is very commonly used. The days that you

Thank you Mister Micawber and Clive.

If I have headache, can I say, "I feel ill because of headaches"; or "I feel sick because of headaches"

Your ill/sick use is OK. More natural:

I feel ill because of a headache"; "I feel sick- I have a headache"

Thank you Mister Micawber.

Do you mean, "I feel sick because of a headache" is incorrect? And it should be only "I feel sick". But if I say, "I feel sick" I think then there is a question arises why I feel sick, so it is better to provide reason beforehand. Am I right?

[Sorry for asking follow-up questions. I am asking in a desperate situation because I must learn such basic thi

Hi,

If your only problem is that you have a headache, we don't usually say 'I feel sick. I have a headache'. We usually just say 'I have a headache'.

I guess it's because a headache is usually seen as a very minor problem.

Clive