John 8:14

ἀπεκρίθη Ἰησοῦς καὶ εἶπεν αὐτοῖς Κἂν ἐγὼ μαρτυρῶ περὶ ἐμαυτοῦ, ἀληθής ἐστιν ἡ μαρτυρία μου, ὅτι οἶδα πόθεν ἦλθον καὶ ποῦ ὑπάγω· ὑμεῖς δὲ οὐκ οἴδατε πόθεν ἔρχομαι ἢ ποῦ ὑπάγω.
Rough Word-by-word:
He answered Jesus and he said to them, "Even if I I might testify concerning myself, true is the testimony of me, because I know from where I came and where I go; you all but not you all know from where I come or where I go."

Smooth Translation:
Jesus answered and said to them, "Even if I might testify concerning myself, my testimony is true because I know where I came from and where I am going, but you do not know from where I come or where I am going."

ἀπεκρίθη verb aorist passive indicative 3rd singular from ἀποκρίνομαι (I answer) "he answered

Ἰησοῦς proper noun nominative singular masculine "Jesus"

καὶ conjunction "and"

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

αὐτοῖς pronoun dative plural masculine "to them"

Κἂν conjunction "and if, even if"

ἐγὼ pronoun nominative 1st singular "I"

μαρτυρῶ verb present active subjunctive 1st singular from μαρτυρέω (I testify) "I might testify"

περὶ preposition with genitive "concerning"

ἐμαυτοῦ reflexive pronoun genitive singular masculine "myself"

ἀληθής adjective nominative singular feminine "true"

ἐστιν verb present indicative 3rd singular from εἰμί (I am) "[she] it is"

ἡ definite article nominative singular feminine "the"

μαρτυρία noun nominative singular feminine "testimony"

μου pronoun genitive 1st singular "of me"

ὅτι conjunction "that, because"

οἶδα verb perfect active indicative 1st singular from εἴδω (I know) "I know" (note: this verb, though perfect, is translated as a present)

πόθεν conjunction "from where"

ἦλθον verb aorist active indicative 3rd singular from ἔρχομαι (I come, I go) "I came"

καὶ conjunction "and"

ποῦ adverb "where"

ὑπάγω verb present active indicative 1st singular from ὑπάγω (I lead, I go) "I go"

ὑμεῖς pronoun nominative 2nd plural "you all"

δὲ post positive conjunction "and, but"

οὐκ adverb of negation "not"

οἴδατε perfect active indicative 2nd plural from εἴδω (I know) "you all know"

πόθεν adverb "from where"

ἔρχομαι verb present middle deponent indicative 1st singular from ἔρχομαι (I come, I go) "I come"

ἢ conjunction "or"

ποῦ adverb "where"

ὑπάγω verb present active indicative 1st singular from ὑπάγω (I go, I lead) "I go"