SB 1.15.1

sūta uvāca
evaṁ kṛṣṇa-sakhaḥ kṛṣṇo
 bhrātrā rājñā vikalpitaḥ
nānā-śaṅkāspadaṁ rūpaṁ
 kṛṣṇa-viśleṣa-karśitaḥ
Word for word: 
sūtaḥ uvāca — Sūta Gosvāmī said; evam — thus; kṛṣṇa-sakhaḥ — the celebrated friend of Kṛṣṇa; kṛṣṇaḥ — Arjuna; bhrātrā — by his elder brother; rājñā — King Yudhiṣṭhira; vikalpitaḥ — speculated; nānā — various; śaṅka-āspadam — based on many doubts; rūpam — forms; kṛṣṇa — Lord Śrī Kṛṣṇa; viśleṣa — feelings of separation; karśitaḥ — became greatly bereaved.
Translation: 
Sūta Gosvāmī said: Arjuna, the celebrated friend of Lord Kṛṣṇa, was griefstricken because of his strong feeling of separation from Kṛṣṇa, over and above all Mahārāja Yudhiṣṭhira’s speculative inquiries.
Purport: 

Being too much aggrieved, Arjuna practically became choked up, and therefore it was not possible for him to reply properly to the various speculative inquiries of Mahārāja Yudhiṣṭhira.