आचार्याः पितरः पुत्रास्तथैव च पितामहाः। मातुलाः श्चशुराः पौत्राः श्यालाः सम्बन्धिनस्तथा ॥

āchāryāḥ pitaraḥ putrās tathaiva cha pitāmahāḥ mātulāḥ śhvaśhurāḥ pautrāḥ śhyālāḥ sambandhinas tathā

Teachers, fathers, sons, as well as grandfathers, mother's brothers, fathers-in-law, grandsons, brothers-in-law, and other relatives.

In plain words: Arjuna lists who is standing there: teachers, fathers, sons, grandfathers, uncles, fathers-in-law, grandsons, brothers-in-law and other relatives.