So far, the exact origins of the different fish species have not been entirely identified.
Very little is known to the exact origin of the tone Page used, or how/why it was done.
It is difficult to find an exact origin of the phrase "the color line".
No one knows the exact origins of the rocking chair.
The home's exact origins have yet to be fully explained.
The exact origin of bridge is not known with certainty.
The exact origins of the breed are hard to determine.
The exact origins of the deal will probably never be known.
The exact origins of the expression have not been clearly established.
The exact origin of the name has not been explained.
