"But that's the only variable you'll have to go out and get yourself," he said.

After all, anyone in the oil business will, with time as the only variable, eventually be out of business.

New taxes are not the only variables upon which the plan is built.

But then the current wasn't the only variable here, was it?

The only variable is how much water to run through them.

Thus the only real variable is the frequency of the power supply.

Training levels are actually not the only variable of performance.

We might, but the course itself is not the only variable which can be changed.

Unfortunately, the cost of the equipment is not the only variable in the equation.

"It's the only variable that has changed since we became vampires."