Knime: If Contains Statement

I’m trying to familiarize myself with column expressions node but having difficulties, can someone help me write out an “if contains” statement?

I’d like to say:

if column(A) contains category or value or data then column (B) else

I know that I can do the same thing in rule engine and I was able to accomplish this statement in that node but I really want to understand column expressions node and how to write statements in it.

Thank you for your time!