John 4:54

Τοῦτο πάλιν δεύτερον σημεῖον ἐποίησεν ὁ Ἰησοῦς ἐλθὼν ἐκ τῆς Ἰουδαίας εἰς τὴν Γαλιλαίαν.

Rough Word-by-word:
This again [the] second sign he did the Jesus when he came from the Judea into the Galilee.

Smooth Translation:
This sign was again the second Jesus did when he came from Judea into Galilee.

Notes:
Does the adverb πάλιν modify the participle ἐλθὼν or the understood verb was that goes with the adjective δεύτερον in the predicate position? If it modifies the participle it would read, "...when he came again from Judea into Galilee."

Τοῦτο demonstrative pronoun accusative singular neuter "this"

πάλιν adverb "again"

δεύτερον adjective accusative singular neuter "second" (note: predicate position)

σημεῖον noun accusative singular neuter "sign"

ἐποίησεν verb aorist active indicative 3rd singular from ποιέω (I do) "he did"

ὁ definite article nominative singular masculine "the"

Ἰησοῦς proper noun nominative singular masculine "Jesus"

ἐλθὼν aorist active participle nominative singular masculine from ἔρχομαι (I come) "when he came"

ἐκ genitive preposition "from/out of"

τῆς definite article genitive singular feminine "the"

Ἰουδαίας proper noun genitive singular feminine "Judea"

εἰς accusative preposition "into/unto"

τὴν definite article accusative singular feminine "the"

Γαλιλαίαν proper noun accusative singular feminine "Galilee"