They said therefore (ειπαν ουν). Second aorist active indicative of defective verb ειπον with α instead of usual ο. Note ουν, inferential here as in verse John 1:21 though often merely transitional in John.

Who art thou? (Τις ει;). Same question as at first (verse John 1:19), but briefer.

That we give answer (ινα αποκρισιν δωμεν). Final use of ινα with second aorist active subjunctive of διδωμ with αποκρισιν from αποκρινομα, above, old substantive as in Luke 2:47.

To those that sent (τοις πεμψασιν). Dative case plural of the articular participle first aorist active of πεμπω.

What sayest thou of thyself? (Τ λεγεις περ σεαυτου;). This time they opened wide the door without giving any hint at all.