Oxford Guide to English Grammar; John Eastwood; Oxford University Press 1994-09
b Look at these examples.
A technical fault caused the delay.
The guests played mini-golf after tea.
We can emphasize different parts of the sentence.
What caused the delay was a technical fault.
What the guests played after tea was mini-golf.
What the guests did after tea was (to) play mini-golf.
What happened after tea was (that) the guests played mini-golf.
a We cannot use who in this pattern. We must put a noun in front of it.
The people who played mini-golf were the guests.
NOT Who played mini-golf were the guests.
1 Why can't "who played the mini-golf were the guests" be used to emphasize? What's the difference between it and "The people who played mini-golf were the guests"?
2 When no emphasis, it's grammatical, isn't it? We can make such sentences, can't we?