"Do you have Oracle database experience?"
"I think so." (I worked at Oracle for three years.)
"Do you know what 'SQL' [pronounced "see-quel") is?"
"Of course! Structured Query Language."
"Are you sure?"
"I ask because we sent two candidates to the client, and neither of them knew what it was. When the interviewer asked what 'SQL' stands for, the candidate asked, 'Can you spell that?'"