ām is optionally affixed when liṭ (Perfect Tense) follows after these verbs - bhī 'to fear', hrī 'to be ashamed', bhṛ 'to nourish', hu 'to sacrifice' and when ām is affixed, the effect is as if there were ślu elision and the roots belonged to hvādi class.,
The effect of श्लु is to cause reduplication by rule 6.1.10. As विभयाञ्चकार or विभाय, जिह्रवाञ्चकार or जिह्राय, विभराञ्चकार or बभार, जुहवाञ्चकार or जुहाव.,