So long time (τοσουτον χρονον). Accusative of extent of time.

And dost thou not know me? (κα ουκ εγνωκας με;). Perfect active indicative of γινωσκω. Jesus patiently repeats his language to Philip with the crisp statement: "he that hath seen me hath seen the Father" (ο εωρακως εμε εωρακεν τον πατερα). Perfect active participle and perfect active indicative of οραω, state of completion.

Thou (συ). Emphatic--After these years together.