In many regular augmented forms, the most visible active/passive distinction is the penultimate vowel.
Word / formMeaning / explanation
مُكْرِمٌ / مُكْرَمٌone who honours / honoured.
مُجْتَنِبٌ / مُجْتَنَبٌavoider / avoided.
مُتَقَبِّلٌ / مُتَقَبَّلٌacceptor / accepted.
مُسْتَنْصِرٌ / مُسْتَنْصَرٌseeker of help / one from whom help is sought.
Both can start with mīm carrying ḍammah; the initial mīm alone therefore does not identify the voice.