Whether the race will start on time or not has been a matter of speculation for days.

Who these soldiers are and where they have gone will always be a matter of speculation.

Just what and how much, was a matter of pure speculation.

Whether Buchanan actually knew what the court would say is a matter of speculation.

Just how far these efforts might have gone is a matter of speculation.

How far the practice may spread is a matter of speculation.

Exactly how soon after this time Jews made their way onto the scene is a matter of speculation.

The subject's identity has long been a matter of speculation.

But I can suggest one as a matter of speculation.

Just why China has kept hands off is a matter of speculation.