Page 645 - Practical English Usage 3ed - Michael Swan, Oxford

624 who ever, what ever etc
These expressions show surprise or difficulty in understanding something.
Who ever is that strange girl with Roger?
What ever are you doing?
However did you manage to start the car? I couldn't. When ever will I have time to write some letters? Why ever did I marry you?
The expressions can also be written as single words: whoever, whatever etc. Note that whose and which are not used with ever in this way.
In an informal style, on earth, the hell (ArnE also in hell) or the fuck (taboo - see 575) can be used instead of ever.
Who on earth is that strange girl? Why the hell did I many you? What the fuck is she talking about?
For the conjunctions whoever. whatever. etc. see 625.
625 whoever, whatever etc
1 meaning and use
Whoever means 'it doesn't matter who', 'any person who', or 'the unknown person who'. Whatever, whichever, however, whenever and wherever have similar 'open' meanings.
A word of this kind has a double function, like a relative pronoun or adverb (see 498.1). It acts as a subject, object or adverb in its own clause. but it also acts as a conjunction, joining its clause to the rest of the sentence. Examples:
Whoever phoned just now was very polite.
I'm not opening the door. whoever you are.
Send it to whoever pays the bills.
Whatever you do. I'll always love you.
Whatever is in that box is making a very funny noise. Keep calm. whatever happens.
Spend the money on whatever you like.
Whichever ofthem you many. you'll have problems.
We're free all next week. You'll be welcome whichever day you come. However much he eats. he never gets fat.
People always want more, however rich they are. However you travel. it'll take you at least three days.
Whenever I go to London I try to see Vicky. You can come whenever you like. Wherever you go, you'll find Coca-Cola.
2 whoever, whichever and whatever. subjects and objects
Whoever, whichever and whatever can be the subjects or objects of the verbs in their clauses. (Note that whomever is not used in modem English.)
Whoever directed this film, it's no good. (subject of directed)
Whoever you many, make sure he can cook. (object of marry)
Whatever you say, I don't think he's the right man. (object of say) •
whoever, whatever etc 625
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