misfiring cylinders 2, 3, 4 on my 03 celica

My check engine light came on so I took it to a mechanic he said it was misfiring and that I should replace my sparkpugs and ignition coils on cylinders 2, 3, 4 so I did but my car still feels sluggish and the light came back on but now he said that my oxygen sensor was bad

So my question is can a oxygen sensor cause sluggish car and multiple misfires?