Rule 3 : After the verbs "Say / suggest / propose / speak / Explain / reply / complain / talk / listen / write" the proposition "to" should be used if any object is used.
Ex : He did not reply to me.

Rule 4 : After the verbs " complain / talk / listen / write" the proposition "to" should be used if any object is used.
Ex : You never wrote to me.