Τί κοινότατον; ἐλπίς. καὶ γὰρ οἷς ἄλλο μηδέν, αὕτη πάρεστι → What is most common? Hope. For those who have nothing else, that is always there.
Use P. and V. ὁ εἴσω, ὁ ἐντός (adv.), ὁ ἔσω.