Question

There are people seated around a round table with a rotatable top. Each person ordered an entree and has an entree in front of him but it turns out that for all the people on the table, they have the wrong entree in front of them. Prove that you can rotate the table such that at least two people will receive the correct entree in front of them.
I know I'm supposed to use the pigeonhole principle but I don't know what the pigeons and holes are. Please help me.