ὑπακούσατε δεξάμεναι θυσίαν καὶ τοῖς ἱεροῖσι χαρεῖσαι → accept my sacrifice and enjoy these holy rites | hearken to our prayer, and receive the sacrifice, and be propitious to the sacred rites | hear my call, accept my sacrifice, and then rejoice in this holy offering I make

[PatSer]

I wonder what would be the singular form of this sentence : ὑπακούσατε δεξάμεναι θυσίαν καὶ τοῖς ἱεροῖσι χαρεῖσαι.
(hearken to our prayer, and receive the sacrifice, and be propitious to the sacred rites) (Aristophanes, Clouds 263 ff.)

If they would have prayed to only one god could they say:
ὑπάκουσον δεξαμενή θυσίαν καὶ τοῖς ἱεροῖσι χαρεῖσα

Thank you in advance

[spiros]

I can find these translations too:
accept my sacrifice and enjoy these holy rites
hear my call, accept my sacrifice, and then rejoice in this holy offering I make

Your use of singular for the verb and δεξαμενή/χαρεῖσα is correct but I am not sure if it makes sense in anything apart from the verb. For example, "δεξαμεναί" in the plural form is idiomatic for veins.

Aristophanes,  Clouds, line 262
http://www.faenumpublishing.com/uploads/2/3/9/8/23987979/aristophanes_clouds_a_dual_language_edition_-_johnston.pdf
Les Nuées d'Aristophane (bilingue) (1 - 500)

[PatSer]

I see.
So what would be the sentense if it starts with : ὑπάκουσον ?
ὑπάκουσον ... ?

[spiros]

I guess you can only change the verb (given that the plural is due to addressing the Clouds further ahead the passage "ἔλθετε δῆτ᾽ ὦ πολυτίμητοι Νεφέλαι").

[PatSer]

Yes, if I can only change the verb, the sentence doesn't make sense anymore. Speaking to one cloud ;) for instance, could I use several imperative forms like :
ὑπάκουσον, δέξαι θυσίαν καὶ τοῖς ἱεροῖσι χάρηθι ?