b) When's = is My birthday's = is
When is your birthday ? My birthday is on....
c) What's = is It's = is Kylie's = génitif
What is on the floor ? It is the pencil case of Kylie.
d) grandmother's = génitif She's = has
Yesterday it was the day of grandmother.... She has got...
a) Today it's Mark's birthday
b)..Barack Obama's statue