What's the difference between 'except' and 'except for'.

[Infin1ty]

Hello everyone,

I'd like to know: What's the difference between 'except' and 'except for' if any. When to use 'except' and when to use 'except for'? In the below sentence in italic:

He has few friends except us.

Could I also say: He has few friends except for us? And what if I place 'except' by 'apart from' or 'besides'? Will the sentence remain the same meaning as it was? Many thanks. :)
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