99 corolla burning oil

I have a 99 corolla with 140,000 miles and it is burning oil about 1 quart every 2 weeks. There is no spotting on the garage floor.

Common problem with that generation Corolla.
Do a Google search using the term "Corolla oil consumption problem".
I maintain a fleet of 30+ 1998 thru 2002 Corollas and 7 of them have the oil consumption problem.
Some of them started at 90,000 miles, others didn't start using oil until they reached 200,000 miles.
One of the effected Corollas spun a rod bearing at 225,000 miles. I replaced the bad engine with a used unit I had on hand (from a wrecked Corolla).
You will have to keep adding oil or get rid of the car.

By the way, 2003 on up Corollas are not effected.
We have an '03 with 330,000 miles on it and it doesn't use a drop of oil.

Good luck!