Need help!!

I have a x reg or 2000 Toyota Corolla 1.4 Gs. I have a 02 sensor error code. On this particular model does it only have one 02 sensor or does it have two? Upstream and downstream? Only reason why I ask because i dont have the manual handbook. Conor
Sorry that's not a common North American motor. But just look at you exhaust. For 2 you will have one dowm pipe. Between the exhaust manifold and the catalytic converter would be upstream. On after the cat will be a down stream one. Hope this helps.