Google Sheets using AVERAGEIF with specific cells

I am trying to get the average of percentages in every other cell, excluding those cells with a 0. I tried this formula.

=AVERAGEIF(C2,E2,G2,I2,K2,M2,O2,Q2,S2,U2,W2,Y2,AA2,AC2,AE2,AG2,AI2,AK2,AM2,AO2,”<>0″)

I get this error. “Wrong number of arguments to AVERAGEIF. Expected between 2 and 3 arguments, but got 21 arguments.”

What am I doing wrong? Thank you for your help!