εἰρήκει δὲ ὁ Ἰησοῦς περὶ τοῦ θανάτου αὐτοῦ· ἐκεῖνοι δὲ ἔδοξαν ὅτι περὶ τῆς κοιμήσεως τοῦ ὕπνου λέγει.

1. εἰρήκει
   he had said
   had said
2. δὲ
   but
   and
3. ὁ
   the
4. Ἰησοῦς
   Jesus
5. περὶ
   about
   concerning
6. τοῦ
   of the
   the
7. θανάτου
   death
   of death
8. αὐτοῦ
   his
9.  
   ·
    
10. ἐκεῖνοι
    those
11. δὲ
    but
    and
12. ἔδοξαν
    seemed
    they seemed
13. ὅτι
    that
    because
14. περὶ
    about
    concerning
15. τῆς
    of the
    the
16. κοιμήσεως
    sleep
    rest
17. τοῦ
    of the
    the
18. ὕπνου
    sleep
19. λέγει
    says
20.  
    .
     

Jesus had said this about his death, but they thought that he was speaking about natural sleep.