John 2:21

ἐκεῖνος δὲ ἔλεγεν περὶ τοῦ ναοῦ τοῦ σώματος αὐτοῦ.

Rough Word-by word:
that But he was saying concerning the temple the of body of him.

Smooth Translation:
But he was saying that concerning the temple of his body.

ἐκεῖνος demonstrative pronoun "that"

δὲ conjunction "and/but"

ἔλεγεν verb imperfect active indicative 3rd singular from λέγω (I say) "he was saying"

περὶ prepostion with genitive "concerning"

τοῦ definite article genitive masculine singular "the"

ναοῦ noun genitive masculine singular "temple"

τοῦ definite article genitive neuter singular "the"

σώματος noun genitive neuter singular "of body"

αὐτοῦ pronoun genitive masculine singular "of him"