I found it in a Grammar quiz online which I forget where it is:
Mr Jones ____ at the meeting, but he had to cancel because of his illness.
a) was speaking
b) was to speak
c) was to have spoken
The answer is c, and I am Ok with it, but I don't know why b isn't. Can't I say someone was to do something, but he could't somehow?
Best Answer
B and c are both fine. The difference is not in the circumstances described: as with most uses of the perfect, the difference is in how the speaker is choosing to refer to the events. In c) the temporal focus is after the meeting; in b) the temporal focus is not specified - might be now, or might be just before the meeting.