No one may ever know, exactly.
However, the true cause remains elusive, and no one may ever know what really happened.
But if the butterfly disappears, no one may ever know for sure.
"I knew that they could imprison me and that no one may ever know my story," she said.
No one may ever know whether the convergence of Mrs. O'Leary's cow and a lantern started the Great Fire of Chicago on Oct. 8, 1871, even though it is known that the blaze began in or near the O'Leary barn.
No one may ever know exactly what happened to Woods, and the book is fiction - keep repeating that with each turned page - but it provides invaluable insight into the life and times of Woods, even if the intimate details described are not verified, or meant to be.
No one knows for sure -- no one may ever know -- what happened, except that Kevin Dare let loose the pole and came straight back down, headfirst, and crushed his skull on the eight-inch-deep steel casing where he had planted the pole on takeoff.
Most discouraging, perhaps, is the likelihood that no one may ever know what sealed MPL's fate or whether some undiscovered flaw in current designs makes upcoming Mars missions anything more than gremlin bait.
