Student: What [is the definition of] had?
Me: It is the past tense of the verb to have.
S: What[is the definition of] have?
Me: To have is to own something. For example, I own a pen means I have a pen.
S: What [is] own?
Me: When something belongs to you, like a car. You could say I own a car or I have a car or a car belongs to me. They all mean the samething.
S: What[is] belong?
Me: To have.