Ecce 41: Perfect Active Infinitives vs Present Infinitives Match correct meanings. REMEMBER, perfect active infinitives are based on the 3rd principle part plus ISSE. Please play a couple of times to see all the forms. Tools See a list of terms used in these activities. Matching Activities created by: Ginny Lindzey This activity was created by a Quia Web subscriber. To learn how to make your own, just like this, click here.