Knew that he had been a long time (γνους οτ πολυν ηδη χρονον εχε). How Jesus "knew" (γνους, second aorist active participle of γινωσκω) we are not told, whether supernatural knowledge (John 2:24) or observation or overhearing people's comments. In ηδη εχε we have a progressive present active indicative, "he has already been having much time" (χρονον, accusative of extent of time).

Wouldest thou be made whole? (Θελεις υγιης γενεσθαι;). "Dost thou wish to become whole?" Predicate nominative υγιης with γενεσθα (second aorist middle infinitive). It was a pertinent and sympathetic question.