After the verb dā 'to give', preceded by aṅ , and when not meaning 'to open the mouth', the ātmanepada affix is used, even when the fruit of the action does not accrue to the agent.,
The root दा is generally both Parasmaipadi and Atmanepadi (see Sutra. 72). But when preceded by the preposition आ, it is restriced to the atmanepada As विद्यामादत्ते 'he acquires knowledge.' But when it means \to widen the mouth\ whether actually or metaphorically, it is parasmaipadi. As आस्यं व्याददाति. 'He expands his own mouth.'
Vart:- The prohibition also applies when the action is similar to the act of opening the mouth. As विपादिकां व्याददाति 'he opens the tumour.' कूलं व्याददाति नदी 'the river breaks the bank.'
Vart:- When the action does not affect the agents' own body the verb is atmanepadi, as व्याददतेपिपीलिकाः पतंगस्य मुखम्, 'the ants open the mouth of a locust.',