01 which?                              dore desuka?
02 which is your book?                 dore ga anata no hon desuka?
03 which is mine?                      watashi no wa dore desuka?
04 which is better one?                dore ga iihoo desuka?
05 which do you want?                  dore ga hoshii desuka?
06 which is right?                     dore ga tadashii desuka?

07 when?                               itsu desuka?
08 till when(how long)?                itsu made desuka?
09 when are you coming?                itsu ki-masuka?
10 when are you leaving?               itsu tachi-masuka?