if condition in Linux

I am trying to write one if condition in Linux.

I have a variable : $check_mrp . I want to check if this variable is not equal to either of the following three values : WAIT_FOR_LOG or APPLYING_LOG or WAIT_FOR_GAP then echo message : "Please start the Manged Recovery Process".

For example if variable value is equal to any of the three (WAIT_FOR_LOG or APPLYING_LOG or WAIT_FOR_GAP) then it should not echo the message since services are running.