John 7:38

ὁ πιστεύων εἰς ἐμέ, καθὼς εἶπεν ἡ γραφή, ποταμοὶ ἐκ τῆς κοιλίας αὐτοῦ ῥεύσουσιν ὕδατος ζῶντος.

Rough Word-by-word:
The one believing into me, just as she said the scripture, rivers out of the belly of him they will flow of water of living.

Smooth Translation:
The one believing in me, just as the scripture said, out of his heart will flow rivers of living water.

ὁ definite article nominative singular masculine "the"

πιστεύων present active participle nominative singular masculine from πιστεύω (I believe) "one believing"

εἰς accusative preposition "into, unto"

ἐμέ personal pronoun accusative 1st singular "me"

καθὼς compound conjunction "just as"

εἶπεν verb aorist active indicative 3rd singular from λέγω (I say) "he said"

ἡ definite article nominative singular feminine "the"

γραφή noun nominative singular feminine "writing, scripture"

ποταμοὶ noun nominative plural masculine "rivers"

ἐκ genitive preposition "out of, from"

τῆς definite article genitive singular feminine "the"

κοιλίας noun genitive singular feminine "bosom, womb, belly, innermost part"

αὐτοῦ pronoun genitive singular masculine "of him"

ῥεύσουσιν verb future active indicative 3rd plural from ῥέω (I flow) "they will flow"

ὕδατος noun genitive singular neuter "of water"

ζῶντος present active participle genitive singular neuter from ζάω (I live) "of living"