Matching Pairs characteristics of two topicOnline version define which characteristics belong to the past simple or the present perfect simple by Silvia Pedraza 1 it is used to talk about an action that has already ended 2 it´s auxiliaries are have and has 3 it´s assistant is did 4 it is talking about experiences 5 past participle of theverb past simple Present perfect simple verb past simple assistant Present perfect simple auxiliaries present perfect simple